Why should you prime?

Priming of subfloors/substrates is key to ensuring the selected smoothing underlayment can perform to its optimum. It improves the flow and workability of the smoothing underlayment. There are three basic reasons why priming is important. Firstly, priming reduces the absorbency of the floor; secondly it increases adhesion and finally, correct priming acts as an interface between materials preventing failure by reaction. The simple process of using the appropriate primer will minimise issues and result in:

  1. A smoother underlayment
  2. A stronger underlayment
  3. A reduction in labour time
  4. A surface fit to lay the thinnest of decorative floor coverings to

Underfloor Heating

Various underfloor heating manufacturers exist including Warmup who offer a range of systems across the different types, including Sticky Mat and Total-16. We recommend that you always refer to the manufacturer’s instructions when installing underfloor heating.

It is becoming increasingly common to come across floors with underfloor heating systems incorporated. It is important to note the following points and check the underfloor heating before you begin work.

Where warm water underfloor heating systems are incorporated, they must have been fully commissioned and brought up to their maximum temperature, and ideally switched off 48 hours before the application of UltraFloor products. It is important to establish that the commissioning of the system has been carried out, consult the underfloor heating manufacturer for confirmation. In the absence of other heat sources, the underfloor heating may be set to ‘cutback’ position to achieve an air temperature of 15°C. Any expansion or movement joints must be carried through to the finished floor surface.

The cables of radiant electrical underfloor heating systems must be secured to a sound, strong mechanically fixed cement faced backer board. UltraFloor products may also be used where electrical underfloor heating is used over cementitious or calcium sulphate subfloors. In all cases our smoothing underlayments must be applied at a minimum thickness of 5mm above the cables for resilient, textile and timber applications and a minimum of 3mm for applications of stone, ceramic or porcelain products.

Warm water systems fixed within pre-formed insulation panels must be mechanically fixed to the existing subfloor/substrate these must be sound and solid with no movement. The panels should be primed depending on the porosity and type. In all cases our smoothing underlayments must be applied at a minimum thickness of 5mm above the cables for resilient, textile and timber applications and a minimum of 3mm for applications of stone, ceramic or porcelain products.

There is no requirement to commission warm water systems fixed within pre-formed insulation panels or radiant electrical underfloor heating systems before the application of UltraFloor products. These systems should be commissioned 7 days after the UltraFloor products have been applied. To commission these systems the heating should be increased 5°C per day from ambient until the maximum operating temperature has been reached, and then decreased back down again by 5°C per day.

The Instarmac CPD – Specifying Tiling to Underfloor Heating Systems – will provide you with an understanding of the benefits of heated tiles and the types of system available.  It will also cover key design and specification considerations and product choices for tiling to underfloor heating and selecting appropriate materials.  It will teach you how to confidently specify typical tiling system build-ups for underfloor heating, and you should also understand the importance of warranties and confidence in complete performance systems. Please visit ultratilefix.co.uk or call 01827 254402 for more information.

Pre-smoothing of Subfloors/Substrates

Where there is an absence of a damp proof course and provided there is no risk of hydrostatic pressure, pre-smoothing can be carried out. UltraFloor Level IT Two, UltraFloor Level IT Bond, UltraFloor Level IT Top and UltraFloor Level IT Base are all suitable for pre-smoothing use, please refer to their respective datasheets for further guidance.

Wear Surface/Surface Finish

When installing a wear surface ensure that the subfloor/substrates has been tested for moisture, any contamination or laitance has been removed, prime if required and check for underfloor heating. Both UltraFloor Level IT Top and UltraFloor Level IT Super Flex 30 may be used as a finished wear surface. Please refer to their respective datasheets for further guidance.

 

The drying characteristics of cementitious smoothing underlayments

The drying characteristics of cementitious smoothing underlayments are directly influenced by ambient air and floor temperatures. Cement within the smoothing underlayment cures through a process of hydration using moisture. Extreme site conditions can affect this process i.e. below 5°C and above 30°C.

Ideal ambient air and floor temperatures for application are between 10°C and 22°C. These temperatures should be maintained throughout application and curing periods. Outside of these temperatures consideration should be given to the following guidelines for good practice. Floor temperatures will be slower to respond to ambient air temperature so should be considered in advance.

High humidity and low temperature prolongs evaporation of moisture from the freshly applied smoothing underlayment and therefore extends drying times. This may ultimately delay installation of floor coverings. In such conditions planned heating (not gas heating) may be required before, during and after application of the product in order to promote ideal site conditions. Heat should be directed into the air not direct to the floor creating hot spots. Good ventilation without direct drafts will also assist removal of moisture in the air from the building. Failure to adopt such practices in such adverse site conditions may result in damp patches, slow drying and potential surface bleed within the curing smoothing underlayment.

Low humidity and high temperature conditions will speed up drying by fast removal of moisture from freshly applied smoothing underlayment. Such conditions may cause rapid loss of moisture, required for the curing process, leading to irregular structure and strength build up. Such tensions within the drying smoothing underlayment could leave hairline surface defects. Under such conditions, smoothing underlayments should be protected from direct sunlight and drafts across its surface. Good air flow within the build without causing drafts is essential to reduce high temperature build up.

 

An A-Z of floor coverings

There is a vast array of final floor coverings available, the following describe each of the most popular kinds:

Carpet

A textile floor covering typically consisting of an upper layer of pile attached to a backing.

Cork

The bark of a cork oak tree which is ground into sheets that are used as tiles to create a floor covering.

Engineered Wood

Engineered wood is man-made/manufactured.

Laminate

A multi-layer synthetic flooring which is fused together using a lamination process.

Linoleum (Lino)

A floor covering made from materials including solidified linseed, pine rosin, ground cork dust, wood flour and mineral fillers such as calcium carbonate. A burlap or canvas backing is most commonly used.

LVT (Luxury Vinyl Tile)  

LVT is made of a series of layers including a photographic and the flooring’s primary component, PVC. The product offers a look of real wood or stone flooring.

Paint

Either a water or resin based decorative surface coating that others a wear proof finish.

Parquet

This floor covering is made of small blocks of timber that are usually adhered to the subfloor/substrate using a bitumen adhesive. Parquet is often laid in a herringbone pattern.

Raised Access Flooring

A raised surface providing an elevated structural floor above a solid substrate, creating a hidden void for the passage of mechanical and electrical services.

Resin

A hard wearing plastic surface, created by mixing together a selection of ingredients. The chemical reaction creates a highly durable finish. Resin is ideal for the heaviest of use areas.

Rubber

Can be made from either natural tree rubber or from synthetic materials, including recycled vehicle tyres.

Solid Wood

Solid wood flooring planks milled from a single piece of timber.

Tile

A hard wearing material such as ceramic, stone or glass available in various sizes and shapes.

Vinyl

PVC chips are formed into solid sheets of different thicknesses by heat and pressure.

UltraFloor European Standards explained

All UltraFloor smoothing underlayments, repair and finishing compounds and our damp proof membrane are fully CE classified, their ‘Declaration of Performance’ certificates can be downloaded at the click of a button from ultra-floor.co.uk or via our Product Planner App.

The European Standards explained:

BS EN 13318:2000 states the definition of a screed as:

Layer or layers of screed material laid in situ, directly onto a base, bonded or unbonded, or onto an

intermediate layer or insulating layer, to obtain one or more of the following purposes:

– to obtain a defined level;

– to carry the final flooring;

– to provide a wearing surface.

BS 8204-1:2011 gives recommendations for the design and laying of concrete bases and cementitious levelling screeds to receive in situ floorings. It also gives recommendations for constituent materials, design, work on site, inspection and testing of concrete bases that are to receive in situ wearing screeds.

BS EN 13813:2002 is entitled ‘Screed material and floor screeds – Screed material – Properties and requirements’.

It defines for fresh screed material the performance related to setting time, consistency, pH value and for the hardened screed material, compressive strength, flexural strength, wear resistance, surface hardness, resistance to indentation, resistance to rolling wheel, shrinkage and swelling, modulus of elasticity, bond strength, impact resistance, reaction to fire, acoustic performance, thermal resistance and chemical resistance.

Cementitious smoothing underlayments (CT) are classified on both compressive (C) and flexural (F) strength and abrasion resistance (AR*) where relevant e.g. CT C35 F6 AR0.5.

*abrasion resistance, in the UK for wear resistance use British Cement Association test.

BS EN 8203:2017 titled: Installation of resilient floor coverings – code of practice, provides recommendations for installation of cork, linoleum, plastics and rubber floor coverings, as well as including recommendations for bases.

BS EN 5325:2001

This British Standard provides recommendations for the installation of textile floor coverings in new or existing buildings. It covers all products composed of textile material with a pile or non-pile use surface, and includes the laying of carpet tiles, either with the use of a permanent adhesive or a tackifier. It details suitable methods of design and installation and advises on the selection of the materials required for their implementation.

BS EN 8201:2011

Code of practice for installation of flooring of wood and wood-based panels. It gives recommendations and guidance on the material, environment and installation variables that combined have a fundamental effect on the performance and serviceability of finished wood flooring. It outlines the most up-to-date specifications involved in laying flooring and illustrates typical constructions on which it might be laid.

 

Underfloor Heating Preparation Guidance

Various underfloor heating manufacturers exist including Warmup who offer a range of systems across the different types, including Sticky Mat and Total-16. We recommend that you always refer to the manufacturer’s instructions when installing underfloor heating.

 

It is becoming increasingly common to come across floors with underfloor heating systems incorporated. It is important to note the following points and check the underfloor heating before you begin work.

 

Where warm water underfloor heating systems are incorporated, they must have been fully commissioned and brought up to their maximum temperature, and ideally switched off 48 hours before the application of UltraFloor products. It is important to establish that the commissioning of the system has been carried out, consult the underfloor heating manufacturer for confirmation. In the absence of other heat sources, the underfloor heating may be set to ‘cutback’ position to achieve an air temperature of 15°C. Any expansion or movement joints must be carried through to the finished floor surface.

 

The cables of radiant electrical underfloor heating systems must be secured to a sound, strong mechanically fixed cement faced backer board. UltraFloor products may also be used where electrical underfloor heating is used over cementitious or calcium sulphate subfloors. In all cases our smoothing underlayments must be applied at a minimum thickness of 5mm above the cables for resilient, textile and timber applications and a minimum of 3mm for applications of stone, ceramic or porcelain products.

 

Warm water systems fixed within pre-formed insulation panels must be mechanically fixed to the existing subfloor/substrate these must be sound and solid with no movement. The panels should be primed depending on the porosity and type. In all cases our smoothing underlayments must be applied at a minimum thickness of 5mm above the cables for resilient, textile and timber applications and a minimum of 3mm for applications of stone, ceramic or porcelain products.

 

There is no requirement to commission warm water systems fixed within pre-formed insulation panels or radiant electrical underfloor heating systems before the application of UltraFloor products. These systems should be commissioned 7 days after the UltraFloor products have been applied. To commission these systems the heating should be increased 5°C per day from ambient until the maximum operating temperature has been reached, and then decreased back down again by 5°C per day.

 

The Instarmac CPD – Specifying Tiling to Underfloor Heating Systems – will provide you with an understanding of the benefits of heated tiles and the types of system available.  It will also cover key design and specification considerations and product choices for tiling to underfloor heating and selecting appropriate materials.  It will teach you how to confidently specify typical tiling system build-ups for underfloor heating, and you should also understand the importance of warranties and confidence in complete performance systems. Please visit ultratilefix.co.uk or call 01827 254402 for more information.

 

Pre-smoothing of Subfloors/Substrates

Where there is an absence of a damp proof course and provided there is no risk of hydrostatic pressure, pre-smoothing can be carried out. UltraFloor Level IT Two, UltraFloor Level IT Bond, UltraFloor Level IT Top and UltraFloor Level IT Base are all suitable for pre-smoothing use, please refer to their respective datasheets for further guidance.

 

Wear Surface/Surface Finish

When installing a wear surface ensure that the subfloor/substrates has been tested for moisture, any contamination or laitance has been removed, prime if required and check for underfloor heating. Both UltraFloor Level IT Top and UltraFloor Level IT Super Flex 30 may be used as a finished wear surface. Please refer to their respective datasheets for further guidance.

How can you remove contamination and laitance?

Following British Standard 8204 all subfloors/substrates must be free from contaminants that may prevent adhesion such as dust, oils, grease, surface laitance, water soluble adhesive residues and weak smoothing underlayments etc.

Various methods and machines exist which are designed for the preparation, removal and finishing of subfloors/substrates prior to the application of any UltraFloor product. They include STGs, Shotblasters, Planers, Grinders, Multi-strippers and Dust Extractors.

We recommend that you contact The Preparation Group for advice on the appropriate method for your job and hire details www.ppcgroup.co.uk.

Smooth dense surfaces can be roughened by mechanical scabbling to enhance the key.

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How do you test for moisture?

85% of complaints are as a result of moisture, Source: FITA

If a subfloor/substrate has not reached the required level of dryness before a floor covering is laid then residual moisture held between the aggregate and cement (or other binder) will slowly be released, reaching the subfloor/substrate preparation and the floor covering causing damage from beneath.

Testing the moisture of a subfloor/substrate can be relatively straightforward, providing you know what you are assessing and have the appropriate equipment. British Standards are in place and subfloors/substrates should be tested in accordance with the British Codes of Practice BS 8203, BS 5325 and BS 8201. A BS hygrometer box should be used. This will provide a Relative Humidity (RH) reading. A reading above 75%RH is higher than is recommended to lay floors without a surface DPM.

If a moisture reading taken is greater than 75%RH then the subfloor/substrate is considered wet (when laying textile/resilient floor coverings, 65%RH for wood). Provided the subfloor/substrate is suitable to receive moisture protection products either a DPM or a MVS can be used. If using either UltraFloor DPM IT or UltraFloor Suppress IT, follow the product’s respective usage instructions as detailed on the datasheet.

Only as a two coat application, UltraFloor DPM IT may be used on subfloors/substrates where there is an absence of a constructional base DPM provided there is no hydrostatic pressure. UltraFloor DPM IT should not be used in projects where hydrostatic pressure is a concern. In such cases the use of pressure relief drainage and/or external tanking systems must be the primary method of protection against moisture.

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Is your subfloor/substrate suitable?

The suitability of a subfloor/substrate should always be fully assessed before carrying out any preparation or installing a floor covering. British Standard 8204 should be referred to for full guidance and clarification.

The main criteria to be assessed is:

  1. Sound/solid – is the subfloor/substrate strong and stable?
  2. Dry – has the subfloor/substrate dried/cured completely?
  3. Free from contamination – is the subfloor/substrate clean?
  4. Laitance free – is the subfloor/substrate surface free of fines?

If the answer to any of these is ‘no’, then the subfloor/substrate is not suitable to be laid onto and further preparation is required.

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Subfloor/Substrate Types

The UltraFloor range of products are suitable for use on all subfloor/substrate types. These fall into two categories, porous and non-porous, the most common include:

POROUS

  • Concrete
  • Sand:Cement
  • Flooring Grade Plywood
  • Anhydrite

NON-POROUS

  • Epoxy Resin Damp Proof Membrane
  • Power Floated Concrete
  • Flooring Grade Asphalt
  • Porcelain, Ceramic, Quarry or Terrazzo Tiled Floors
  • Steel Mezzanine Decks
  • Access Panels

It is important to establish the type of floor you are laying onto so it can be prepared in the correct way.

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Wall Tiling – Render

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Render

Instructions:
Allow a minimum of 4 weeks for the render to dry. Prior to tiling ensure the render is dust free and is not showing any signs of efflorescence. Weak or friable render should not be tiled onto.

Priming:
It is not normally required with highly flexible adhesives. If in doubt please consult the UltraTileFix Technical Department.

Tiling onto floors with underfloor heating – Electric cable mats

A – Concrete substrate
B – Prime
C – Adhesive
D – Thermal tile backer board
E – Prime
F – Under tile heating mat
G – Prime
H – Level to embed or cable height
I – Prime
J – Apply adhesive (selected upon tile type)
K – Install tiles
J – Grout all joints

There are numerous manufacturers of ‘radiant mat’ electric underfloor heating so always contact them directly for specific advice. The systems consist of electric cables or mats which need to be fixed to the substrate in a prescribed pattern to ensure even heat throughout the floor.

Care should be taken to avoid snagging (therefore damaging the cables when applying adhesive) and thermal shocks when the heating is utilised. There are two options which can be used when installing tiles onto these systems:

  1. Applying a smoothing compound to embed the cables
  1. Applying a smoothing compound to bring to cable height and avoid snagging when applying the tile adhesive

In both cases, the following criteria apply:

  1. The subfloor must be sound, strong, stable and suitable to receive a cementitious smoothing compound.
  1. Any expansion joints in the floor design must be followed through into the finished tile installation and must not be covered over. This is most often between different heated areas and/or substrates.
  1. We recommend that timber substrates should have a suitable backer board mechanically and/or physically bonded prior to installing the electric underfloor heating systems to minimise thermal substrate movement as heating is switched on and off.
  1. Before any preparation or tiling work is carried out the system must be tested to confirm it is fitted correctly and functioning. This should also be done during andafter installation to ensure no damage has occurred.
  1. Substrates must be primed with the UltraTileFix ProPrimer. The priming will usually improve the adhesion of the tape utilised in fixing the cables but if they were already present it is important not to flood the floor with primer. Apply only a thin film.
  1. Select the most appropriate smoothing compound for the substrate. Generally UltraTileFix ProLevel One or ProLevel Fibre is preferred for solid, strong substrates such as concrete or sand/cement. UltraTileFix ProLevel Two for difficult to bond to, dense surfaces such as ceramic tiles or where the substrate is mechanically fixed only e.g. backer boards.

Check with the UltraTileFix Technical Department for the most suitable product.

  1. Apply the selected compound by pouring onto the floor and gently smooth with a straight edge metal trowel. Either cover the highest point of the cables by a minimum 3mm or fill in between the cables without applying compound over the surface (this will enable the tile adhesive to be applied without snagging the cables). Allow the smoothing compound to cure. Time for this will depend on thickness, substrate and conditions.
  1. Apply either (as per instructions for an absorbent cement based floor) and allow to dry. Fix the tiles using a flexible cementitious adhesive. Allow to cure as per datasheet instructions, before grouting with a flexible cementitious grout. Both products should be left to cure for a minimum of 14 days, before gradually bringing up the temperature of the floor in accordance with the manufacturer’s instructions.

Various underfloor heating manufacturers exist including Warmup who offer a range of systems across the different types, including Sticky Mat and Total-16. We recommend that you always refer to the manufacturers instructions when installing underfloor heating.

Visit warmup.co.uk to download Warmup technical guides.

Tiling onto floors with underfloor heating – Warm Water Systems

A – Concrete substrate
B – DPM
C – Insulation
D – Heating pipes
E – Screeds
F – Prime appropriately for the type of screed used
G – Apply adhesive (selected upon tile type)
H – Install tiles
I – Grout all joints

1a. Warm water systems – encased in screed 

These consist of a run of pipes embedded within a pre-laid screed, often calcium sulphate based due to its flowing characteristics. The surface preparation and priming required before laying tiles is the same as for screeds without underfloor heating. Before any tiling is carried out, the following criteria must be met:

  1. The screed must have been left for the minimum cure time before the heating is switched on (this is generally 21 days for sand / cement screeds, and 7 days for calcium sulphate screeds).
  2. The underfloor heating must have been fully commissioned and tested. This is not a simple pressure test but must be a full heat up and cool down of the system. This is normally a 7 day cycle. Only by doing this can any screed weaknesses be identified.
  3. All movement joints must be identified and followed through in the tiling. Screed movement under temperature change is a major cause of tiled floor failure so the need for movement joints is extremely important. Movement joints should be present between all different heating zones, door thresholds, upstands and perimeters.
  4. Traditional cement based subfloors and calcium sulphate screeds must be tested for moisture levels and confirmed to be 75% RH or less using a hair hygrometer. Proprietary cement based screeds may cure and dry at different rates so always check with the manufacturer.
  5. The adhesives and grouts selected must be flexible.
  6. Do not run the heating at high temperatures as this will force dry the adhesive and grout, causing cracking and lifting. Have the heating on at a ‘cutback’ temperature whilst tiling – this means a floor temperature of max 15oC.
  7. Once the tiling and grouting has been carried out the temperature must remain the same for a minimum of 7 days. After this time, the underfloor heating can be brought up to full working temperature slowly. A maximum water temperature increase of 5oC per day is advised.

1b, Warm water systems – fixed within pre-formed insulation panels

This popular alternative system removes the need for a screed by using pre-cut channels in the insulation panel to house the warm water pipes. This system provides a lightweight base option, which can be tiled onto directly. Often the surface of the insulation panel can be faced with an aluminium foil to help spread the heat.  Prior to commencing tiling the following must be met:

  1. All underfloor pre-formed panels must be secured firmly to the substrate and be sound and solid, free from movement. Always consult the manufacturer’s installation instructions.
  2. The underfloor heating must be fully commissioned and pressure tested before tiles are installed to ensure there are no leaks.
  3. Once water pipes have been positioned and within 24 hours prior to applying the tiles, it is advised that all panels are cleaned and ensured dust free. We recommend priming the entire surface of the panels with a neat coat of UltraTileFix ProPrimer including the installed heating pipes and cavities that do not have pipe work in them.
  4. Once the primer has fully cured, tiling can commence using either an S1 or an S2 adhesive. Ensure all cavities within the panels are first filled with the adhesive using a smooth edged trowel.  This will provide a level surface to the panel before finally applying the same chosen adhesive with a notched trowel to the bed thickness required.
  5. Follow the same guidelines as in 1a. Vl. and Vll. to curing of adhesives and grouts and operating the underfloor heating.

A – Substrate
B – Apply DPM if required on newly laid screeds
C – Adhesive as specified by underfloor heating manufacturer
D – Pre-formed underfloor heating panels
E – Prime using UltraTileFix ProPrimer
F – Apply S1 or S2 adhesive
G – Install tiles
H – Grout using a flexible grout

13_UFH_Pipes_2017

 

Various underfloor heating manufacturers exist including Warmup who offer a range of systems across the different types, including Sticky Mat and Total-16. We recommend that you always refer to the manufacturers instructions when installing underfloor heating.

Visit warmup.co.uk to download Warmup technical guides.

Use of UltraTileFix ProFlex CSA on calcium sulphate screeds

Flowable calcium sulphate screeds, also known as anhydrite, hemi hydrite or gypsum screeds, have many advantages over traditional sand/cement screeds such as:

  • Can be laid thinner, reducing weight loadings
  • May be made using industrial by-products so can be environmentally friendly
  • Increased speed of installation as they can be pumped

It is important that calcium sulphate screeds are identified before any tiling installations are carried out because they have different requirements. They may not be visually different from traditional screeds so always enquire, particularly if the screed contains underfloor heating.

Unlike sand / cement and cementitious products, which can still have extremely high tensile and compressive strength whilst retaining a high level of moisture, calcium sulphate screeds need to reach a level of dryness to enable them to perform correctly underneath the tiling. It is essential to know the moisture state of a calcium sulphate floor before commencing tiling.

Moisture testing before application of tiles

The approved standard moisture test method is to use a surface hygrometer. This is an insulated box, fixed to the unheated floor for typically 4 days, after which the moisture in the air, trapped in the box reaches equilibrium. This air is then tested using either an analogue or digital hygrometer. If the reading is less than 75%RH (relative humidity) then the screed is dry enough.

Other indicative test methods may be used to help identify if moisture is a concern or if the screed is close to dry. A simple test is to tape a piece of plastic to the floor for 48 hours. Moisture condensing on the underside of the plastic or a darkening of the screed indicates moisture levels are still significant. The recommended drying times of calcium sulphate screeds, as quoted by the manufacturers, are usually based on drying conditions at 20°C, low air humidity and an open surface with no materials overlaid. This does not represent a typical site scenario so they should not be relied upon.

Underfloor heating within the screed

It is also important to remember that underfloor heating must have been fully commissioned. This does not mean a simple air pressure test but means a full cycle through the heating range. This is necessary to:

  1. Ensure there are no leaks in the system
  2. Identify if any weaknesses are in the screed by showing likely points of cracking and spalling (typically due to poor installation of the screed with heating)
  3. Assist the drying of the screed

If underfloor heating is present there should be expansion strips between the different heating zone areas to enable the screed to move independently, around any perimeters, and at upstands and door thresholds. In all cases these strips should not be tiled over but should be carried through to the upper tiled floor, using a silicone sealant or similar to enable a continuous floor to be achieved. When underfloor heating is present we advise that a polymer modified tile adhesive is used. It is always beneficial to use a rapid set product on these screeds to minimise the migration of moisture between screed and adhesive during curing.

Preparation

Once the above criteria has been completed it is advisable that all screeds are mechanically abraded using a rotary disc to remove laitance and weak upper surface (caused as a result of fines floating to the surface during wet installation) – consult screed manufacturer for their specific requirements.  Poor removal of laitance is often a point of failure when tiling over, so it is essential that laitance is totally removed and all dust and debris is completely vacuumed away to leave a stable, open textured, dust free surface.

Tile adhesive selection

UltraTileFix have developed a calcium sulphate based tile adhesive perfectly suited for use on calcium sulphate screeds.  UltraTileFix ProFlex CSA provides compatibility in its base materials as well as showing the same low tension throughout its curing process.  What’s more it is now rapid drying.

Priming

It is not essential to prime when using UltraTileFix ProFlex CSA as it would be with standard cement based tile adhesives due to its compatibility with the screed.  However it is always good practice and ensures finer dust particles are bonded and sealed.

Image key:

A – Calcium sulphate screed
B – Optional priming
C – Apply UltraTileFix ProFlex CSA
D – Install tiles
E – Grout all joints

Reduce impact sound perception while giving a durable tiled surface with SCHLÜTER®-DITRA-SOUND and UltraTileFix adhesive

Schlüter®-DITRA-SOUND is an acoustic floor system that not only reduces noise, but actually protects the tiled surface, overcoming one of the major problems of tiling onto acoustic floors.

While reducing the impact sound of floor constructions (test values according to BS EN 140-8), Schlüter®-DITRA-SOUND was also specially designed to ensure that the tiled surface is highly durable, bearing loads up to 5kN/m².  It is a bonded impact sound insulation for tile covering, made of a heavy polyethylene mat, which has an anchoring fleece laminated on both sides to bond with UltraTileFix’s ProFlex SP.

At only 3.5mm thick, Schlüter®-DITRA-SOUND also gives a low construction height.

Installation of ceramic tiles to Schlüter®-DITRA-SOUND with UltraTile adhesive:

In order to install Schlüter®-DITRA-SOUND correctly, the substrate must be level, ready to bear weight and free of all substances that may weaken the bond.  Any levelling must be completed prior to the installation.

Picture1

Dry lay individual courses of Schlüter®-DITRA-SOUND making required cuts, ensuring the joints are tightly abutted.  Apply UltraTileFix ProFlex SP thin-bed adhesive over the clean, load bearing substrate with a notched trowel (recommended size 3x3mm or 4x4mm).

Lay Schlüter®-DITRA-SOUND mat into wet UltraTileFix ProFlex SP adhesive, ensuring joints are tightly abutted.  Use a float or roller to press Schlüter®-DITRA-SOUND into the adhesive.

Cut the edge strip Schlüter®-DITRA-SOUND-RSK with a knife (making sure that the tile covering has no direct contact with the wall or any upright construction fixtures after installation).

Picture2

To avoid sound bridges, cover all joints with the self-adhesive joint covering, Schlüter®-DITRA-SOUND-KB.  It is important to protect any installed Schlüter®-DITRA-SOUND by overlaying walking boards while work continues and prior to tiling.  This will prevent damage to the boards and de-bond.  Use Schlüter®-DILEX profiles for neat floor to wall transitions.

The tiles may be installed in the normal way with UltraTileFix ProFlex SP adhesive immediately after the installation of Schlüter®-DITRA-SOUND.

Picture3

50% NOISE REDUCTION:

The impact sound reduction of 13dB achieved by Schlüter®-DITRA SOUND means that the impact sound perception is cut by more than half.

The heavy polyethylene material absorbs much of the impact sound created by walking and substantially reduces the drum roll effect of sound being reflected off hard surfaces.  This makes it ideally suited both for new and refurbishment projects.

As well as providing impact sound insulation, Schlüter®-DITRA SOUND protects the tiled surface by bridging cracks in the substrate which are not expected to widen significantly, ensuring that those cracks are not transferred to the tiles.  As the material is a heavy matting that cannot be compressed, it is suitable for applications of up to 5kN/m².

For applications where the substrate needs to be protected from moisture ingress, eg. bathrooms, Schlüter®-DITRA-SOUND can be combined with Schlüter®-KERDI and Schlüter®-KERDI-COLL to create a bonded waterproofing assembly.

UltraTileFix ProFlex SP is a single part, rapid set tile adhesive specially formulated to achieve enhanced adhesion and flexibility where slight movement or vibration can occur.

The adhesive’s unique qualities make it suitable for fixing glass, porcelain, mosaic and ceramic tiles.  It is available in grey in 20kg and10kg sizes, and white in 20kg.

This information is intended as a guide only and should be used in conjunction with manufacturers’ current technical information and recommendations.

For further information, please call 01827 254402.

Fixing ceramic tiles to SCHLÜTER®-DITRA on timber floors with UltraTileFix adhesive

Schlüter®-DITRA acts as an intermediate substrate system on floors, prior to the fixing of ceramic and natural stone tiles with UltraTileFix adhesive.

As an uncoupling system it is used on timber substrates such as wood-based sheets  and board where possible movement  at board junctions could otherwise lead to the floor tiles cracking. Schlüter®-DITRA  is also  designed for overlaying timber substrates  where a waterproofing system is required, in areas  such as  bathrooms, wetrooms and showers.

Installation of ceramic tiles to Schlüter®-DITRA on timber floors with UltraTileFix adhesive:

Ensure adequate underfloor ventilation.

Remove any existing floor coverings.  The timber floor construction should be load bearing, clean, dry and level.  Re-fix loose boards.  Additional bracing should be used if the floor flexes.

Dry lay the Schlüter®-DITRA and cut to fit before adhering  to the sub-floor.

Using a 3x3mm notched trowel, apply a layer of UltraTileFix ProFlex SP over the floorboards  to a sufficient depth  to secure  the fabric fleece  on the Schlüter®-DITRA underside of the matting.

Picture1

Lay the matting into  the wet/tacky adhesive and press firmly into place, abutting all edges.  If a waterproofing system is required, the mat joints should be sealed with Schlüter®-KERDI-KEBA sealing band and the sealant adhesive Schlüter®-KERDI-COLL.

Picture2

Select UltraTileFix ProFlexSP adhesive and apply into the mat surface to completely fill the dove-tailed square cavities.

Apply additional UltraTileFix ProFlex SP to the filled mat surface with a notched trowel that is appropriate to the size of tile being fixed, ensuring solid bedding of the tiling.  Please note that the minimum tile size where Schlüter®-DITRA is used should be 50x50mm.

Picture3

UltraTileFix ProFlex SP is a single part, rapid set tile adhesive specially formulated to achieve enhanced adhesion and flexibility where slight movement or vibration can occur.

The adhesive’s unique qualities make it suitable for fixing glass, porcelain, mosaic and ceramic tiles.  It is available in grey in 20kg and 10kg sizes, and white in 20kg.

NOTE: Movement joints should be included at room perimeters or where tiling abuts fixed objects.  Tile surface movement joints should be incorporated  over any substrate change and in larger tiled areas, according to industry standards.

This information is intended as a guide only and should be used in conjunction with manufacturers’ current technical information and recommendations.

For further information, please call 01827 254402.

In-depth guide to using UltraTileFix grouts

UltraTileFix offer a comprehensive range of grout products for today’s vast variety of wall and floor applications.

Always select the correct grout for the application depending on the requirements.

The following guide is aimed at identifying the critical points for each stage of grouting to ensure optimum performance of the product.

Guide to successfully using UltraTileFix grouts

There are 3 stages that need to be carried out correctly when using grouts. These are:

1. Mixing the grout
2. Applying the grout
3. Cleaning and finishing off the grout

Preparing to grout

Prior to carrying out any grouting remove all spacers and brush/blow away any loose tile adhesive from the joints. We do not recommend tiling over spacers as this can cause colour variation and will result in only a thin application of grout. Wipe down the tile edges to ensure a clean surface is available for the grout to bond to. Do not allow puddles of water to accumulate in the joint as this will greatly affect the grout performance.

Stage 1 – Mixing the grout

The critical points to remember are to use clean cold water with the correct ratio of powder (as stated on the product’s packaging) and to always use a clean bucket for mixing. When mixing:

• The powder must always be added to the water gradually. DO
NOT pour all the powder in at once.

• Mix the product to attain a smooth lump free consistency. This
can be done using a mixing trowel (or similar) or by the use of a
mechanical whisk. When using a whisk keep the whisk below
the surface and do not use at speeds greater than 300rpm as
this will result in air in the product.

• After initial mixing leave the product to stand for approximately
2 minutes before mixing again. This ensures full reactivity and
wetting of all the components in the grout.

• DO NOT mix more grout than can be used within the stated Pot
Life (please note that Pot Life will be shorter in warmer weather
and when mixing large quantities of grout).

• Ensure that the ratio of water to powder is kept consistent for all
applications on a particular job to ensure consistent colour.

• Under no circumstances add extra water to the grout during
its Pot Life as this will weaken the product and cause colour
variation.

Stage 2 – Applying the grout

The critical points here are to work in small areas concentrating on completely filling the joints to ensure no voids in the grout body, and it is essential that the grout is left to ‘firm’ up before cleaning down. Before applying any grout ensure the tiles are fully secure and do not shift or move under pressure. Do not simply rely on the stated drying times for the adhesive used as this can vary depending upon site conditions. When applying:

• Only apply a small amount of grout onto the tile surface.

• Using a grout float or a squeegee spread to the joints and compact the grout firmly into the joints. Always use the grout float or squeegee at an angle of approximately 30° to the tile, to enable the grout to move freely.

• Apply firm pressure to ensure full compaction. This will normally require applying more grout over the initial application a couple of times. Ensure this is done within the grout’s working time.

• Once fully compacted remove excess grout by using the trowel or squeegee at right angles to the tiles, moving diagonally ensuring minimum contact with the grout lines. Should the grout be disturbed then refill and compact as above. This process should leave only a smear of grout on the tiles.

• Leave the grout to firm before carrying out cleaning.

Please note that there are many different terms used to describe the stage when grouts are ready for wet cleaning. All of them are basically referring to the point when the grout is not readily disturbed and will no longer be ‘dragged’ out of the joint when pulling a damp sponge across, but has not gone to the stage of cure where it is set hard. The time for a grout to firm up will depend on many factors. The material on the tile face is in a thin film and will firm/dry quite quickly. The time for material in the joints to firm up will depend on joint width and depth and the absorbency of the substrate and tile edge. For example, fixed biscuit ceramic tiles with thin joints, on a plastered wall will result in relatively quick firming of the grout as all surfaces can absorb the moisture from the grout. Fully vitrified tiles with wide joint widths on a very dense concrete floor will take considerably longer, as the moisture from the grout needs to evaporate from the exposed surface only.

Stage 3 – Cleaning and finishing off

The critical factors to remember here are ensuring that the grout has reached the correct degree of cure (as per the note above) and that minimal water is used. Excess water will absorb into the grout and often result in the various components in the grout being drawn to the surface causing colour differences.

• When cleaning down you will need a clean sponge and clean water. We do not advise the use of a waterboy as this often results in an excessive amount of water being used.

• When cleaning and finishing, as per the application of the grout, only work in small areas.

• Dampen the sponge with the clean cold water then wring out as much water as possible.

• Wipe over the surface of the tiles and the grout lines. This will remove the majority of grout from the surface of the tiles.

• Rinse out the sponge in clean water to remove the grout particles. Ensure this is done thoroughly.

• Rewet the sponge in clean cold water and wring out as much water as possible.

• Wipe down the joints and neaten the grout lines as well as wiping off any remaining grout residue from the surface of the tiles.

• This may often give the desired final appearance. If further wipe downs are necessary then repeat the process as above, but ensure clean water is used each time.

• Leave the grout to harden in the joints before wiping off any remaining haze from the tile surface using a soft dry cloth.

For further information, please call 01827 254402.

 

PVA for priming – good practice or a bad habit?

Primers play an important role in preparing surfaces, prior to the application of cementitious tile adhesive. They help to reduce the porosity of high absorbent substrates, which prevents the rapid suction of water out of the tile adhesive when applied.

This in turn improves the bond strength at the interface between adhesive and substrate. Where thorough preparation of all substrates is vital to remove friable and weak surface materials, priming, as a part of this operation, aids in consolidating the surface. Due to reactions that occur between plaster-based substrates and cement based adhesives, correct priming acts as an interface between the two materials preventing direct contact and therefore preventing the risk of bond failure by reaction.

It is therefore important that when identifying the requirements for tiling, as much consideration is given to the choice of primer, if required, as is given to the choice of the correct adhesive or grout. Most tile adhesive manufacturers offer specially formulated primers based on acrylic polymers in the main. The recommendations for priming are a key part of the tile adhesive manufacturers’ instructions but often too little attention is paid to these recommendations by the user. It is common practice that PVA liquids are used as a universal alternative. Priming is an area of our industry that is too often misunderstood.

The market is flooded with PVA based products that contain varying levels of PVA polymer. In choosing a general purpose PVA for priming, the varying polymer levels will also vary the film thickness that remains on the surface when the primer has dried. The overall thickness of the dried film will depend on the choice of PVA product and the dilution rate suggested by the supplier. More importantly many PVAs have a tendency to re-soften once dried, when brought back into contact with moisture. This re-softening is the basis of many failures resulting from the use of PVA primers.

Unfortunately, the use of tile adhesive will introduce water to the dried film of PVA and as the cement based tile adhesive cures by hydration it will begin to harden, which in turn will create a stress on the interface with the primer. This crystallisation curing process taking place on a now softened and weak PVA background has a high potential for reducing the overall bond strength between the adhesive and the substrate. The end result is likely to be adhesion failure. The level of the failure depends on the type of PVA used and the film thickness of the PVA polymer left on the surface of the substrate. 

It will also depend on the application – vertical wall applications are more vulnerable as they carry a downward gravitational pull due to the combined weight of adhesive, grout and tile. This will add additional stress to the weak primer interface. However, the effect can still be found on horizontal flooring applications.

While PVAs offer an economic option, for the reasons described, they can considerably increase the risk of failure.

It is therefore advisable to follow manufacturer’s recommendations by choosing the correct primer, which will ensure first time successful fixing. At UltraTileFix we would always recommend the use of an acrylic based primer.

For more information, please call 01827 254402.

Waterproof / tanking systems

A – Concrete substrate
B – Plasterboard
C, D, E, F – Apply tanking system according to application method
G – Apply adhesive (selected upon tile type)
H – Install tiles
I – Grout all joints
J – Seal with silicone

There is a need to waterproof or ‘tank’ a tiling installation when the substrate to which the tiles are to be fixed will either be affected by contact with water or will allow moisture to pass through it. The prerequisite of a tanking system is to waterproof, together with providing strength and flexibility, whilst still enabling tiles to adhere.

Tanking systems, are designed for use on internal applications where intermittent and frequent wetting occurs, such as showers, wetrooms and saunas. Different waterproofing requirements are needed for areas of permanent or prolonged immersion in water such as swimming pools and Jacuzzis.

Tanking systems are suitable for application to most wall and floor substrates, provided they are mechanically secure and stable. If significant flexing or deflection occurs this should be reminded before tanking application.

Select a flexible adhesive, such as UltraTileFix ProFlex SP or ProFlex S2 and grout that are suitable for the chosen tile type and size.

Wall Tiling – Tiled

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Tiled

A – Block work wall construction
B – Existing tiles
C – Prime using UltraTileFix ProPrimer neat
D – Apply adhesive (flexible only should be used)
E – Install tiles
F – Grout all joints

Instructions:

Ideally, existing tiles should be removed and then the substrate can be prepared as required. However, it is accepted that on occasions removal of existing tiles may not be an appropriate method so a ’tile on tile’ installation is necessary. The existing tiles must be securely bonded to a sound stable background that is capable of accepting the weight of the original tiling plus the new tiles. Tiles that sound hollow or loose should be removed and the exposed area primed prior to applying a cementitious repair mortar. Existing tiles should be degreased and then lightly abraded to provide a clean mechanical key.

Priming:
Class as non-porous and refer to chart on pages 10 & 11 of the UltraTileFix_Brochure.

Wall Tiling – Backer board

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Backer board

A – Studwork walls
B – Tile backer board
C – Jointing mesh to reinforce the joints
D – Prime (if using a ready mixed adhesive may not be necessary)
E – Apply adhesive (selected upon tile type)
F – Install tiles
G – Grout all joints

Instructions:
Class as non-porous and refer to chart on pages 10 & 11 of the UltraTileFix_Brochure.

Wall Tiling – Plywood

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Plywood

A – Studwork walls
B – Plywood (it is recommended to seal all exposed plywood to ensure any high/low humidity fluctuations do not cause warping and distortion)
C – Prime (if using a ready mixed adhesive priming may not be necessary)
D – Apply adhesive (selected upon tile type)
E – Install tiles
F – Grout all joints

Instructions:
Plywood boards must be a minimum thickness of 15mm. The grade of plywood used should be suitable for exterior use and may include marine or Class 3 plywood. The boards should be fixed to the framework at a minimum 300mm centres on both horizontal and vertical battens. The plywood must be screwed, not nailed to the framework to ensure a rigid, secure substrate. Any supporting timber framework must be fully seasoned to ensure no warping or twisting occurs after installation.

Priming:
Is not normally required with highly flexible adhesives. If in doubt please consult the UltraTileFix Technical Department.

Wall Tiling – Plasterboard on studwork or solid walls

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Plasterboard on studwork or solid walls

A – Studwork walls
B – Plasterboard (always fix to the paper faced side of the plasterboard
C – Prime (if using a ready mixed adhesive priming may not be necessary)
D – Apply adhesive (selected upon tile type)
E – Install tiles
F – Grout all joints

Instructions:
Plasterboards must be securely fixed to the original substrate to ensure they are firm, rigid and dry. Any supporting timber framework must be fully seasoned to ensure no warping or twisting occurs after installation.

Priming:
Class as porous and refer to char on pages 10 & 11 of the UltraTileFix_Brochure.

Wall Tiling – Plaster / solid walls / skimmed plasterboards

For wall tiling applications it is essential that the wall itself has sufficient inherent strength to hold the proposed tile and the adhesive being used.

The following chart lists the accepted maximum loadings for a variety of wall substrates. In all cases, it is advised that where wall boards, of any type, are used that the manufacturer be consulted for further guidance.

Wall Substrate Maximum tile weight (plus adhesive and grout*)
Gypsum plaster 20kg/m²
Plasterboard (gypsum) unskimmed 32kg/m²
Plywood (exterior grade) 30kg/m²
Gypsum fibre boards 40kg/m²
Tile backer boards 40kg/m²
Glass reinforced cement sheets 50kg/m²

*Typically the weight of the adhesive and grout is 2-4kg per m².

Wall types vary considerably but all have the same basic need to be structurally sound, strong, smooth and level.

It is important to understand that tile adhesives are not designed to be a method of overcoming surface undulations and unevenness.

The specifications for various substrates and their stability are listed below. Should any other substrates be encountered, please contact the UltraTileFix Technical Department.

Plaster / solid walls / skimmed plasterboards

A – Block work wall construction
B – Plaster (do not tile onto bonding/backing plaster)
C – Prime (if using a ready mixed adhesive priming may not be necessary)
D – Apply adhesive (selected upon tile type)
E – Install tiles
F – Grout all joints

Instructions:
A plastered wall must be at least four weeks old prior to tiling to ensure adequate strength build up and suitable dryness. Prior to tiling ensure the plaster is dust free and is not showing any signs of efflorescence. Weak or friable plaster should not be tiled onto. Densely finished, polished or shiny plaster should be ‘roughened’ up to provide a good mechanical key. A stiff bristle brush should be used.

Priming:
Class as porous and refer to chart on pages 10 & 11 in the UltraTileFix_Brochure.

Using a damp proof membrane

A – Sand/cement screed or concrete floor
B – Damp proof membrane
C – Prime using UltraTile ProPrimer neat
D – Apply adhesive (select upon tile type)
E – Install tiles
G – Grout all joints

A surface damp proof membrane (DPM) is a liquid system that when applied to a damp substrate:

  1. bonds strongly to the surface
  2. cures to form a hard layer that controls moisture vapour permeability to the surface

UltraFloor DPM IT, rapid curing primer membrane is a two component, solvent free epoxy resin system for use as a surface DPM and as a screed bonding aid (primer) for industrial flooring applications. It is supplied in a twin pack dual chamber to enable ease of transport and mixing. The product performs by a reaction between the resin and hardener components to give a durable continuous membrane. When mixed the product is a black colour enabling easy identification of the applied areas.

It is suitable for use as a single coat DPM to suppress residual moisture in concrete and sand/cement screed where the moisture levels are 98% RH or less (when tested with a properly calibrated surface hygrometer in accordance with BS 8203). It may be used as a two-coat application on subfloors where there is an absence of a constructional base DPM provided there is no hydrostatic pressure.

UltraFloor DPM IT should not be used in projects where hydrostatic pressure is a concern. In such cases the use of pressure relief drainage and/or external tanking systems must be the primary method of protection against moisture.

Application steps:

  1. All substrates must be prepared to leave a sound, clean and surface dry subfloor. Oils, grease and other contaminants that may hinder adhesion must be removed. This includes release agents used in concrete curing processes as well as laitance, contamination and any weak surface materials. Substrates should be of a minimum 25N/mm².
  2. Apply UltraFloor DPM IT to the substrate by pouring it onto the floor area to be treated. For use as a DPM the product should be spread using a suitable notched towel to determine the correct coverage rate. Over roll the serrations using a short pile roller pre-wetted in UltraFloor DPM IT to ensure a uniform coating is achieved. This should be done immediately following trowelling.
  1. UltraTileFix ProPrimer should be applied neat as a single coat, using a brush or roller. Apply to give a thin uniform coverage with no pooling of the primer. Ensure a complete overall application is achieved. Once dry, the primer will exhibit at light track and is ready to receive smoothing underlayments and tiling adhesives.

Tiling swimming pools / permanently wet areas

Swimming pool construction is governed by the BS 8007: Code of Practice for Design of Concrete Structures for Retaining Liquids. The standard clarifies how such constructions must be carried out and how to test for water tightness. As far as fixing tiles is concerned, it needs to be confirmed that the construction has been carried out correctly and tested before tiling commences. There are also some basic time frame principles:

  • The construction itself must have had a minimum 6 weeks to cure and harden
  • Any further renders or screeds used must have had a minimum of 3 weeks to cure
  • Tiles should be fixed and allowed to fully cure before grouting; usually a minimum of 3 days
  • The construction must then be left for a minimum of 3 weeks before water is introduced (no greater than a depth of 750mm per day)

The methods used to create watertight construction can differ. Ensure the surface to be tiled is suitable to receive a cementitious tile adhesive and is prepared correctly. Preparation must include removal of any laitance from the renders or screeds and cleaning off any mould release agents that may have been used when constructing the shell. Power washing is often sufficient to prepare the surface. Although the adhesives and grouts normally used are classified a water-resistant this does not imply that they will prevent water passing through. This only confirms that they retain their strength and adhesion even when fully immersed. It is critical that the construction is inherently watertight. If a waterproof grout is required, or it is known that aggressive chemicals are to be used for cleaning, or if power wave machines are incorporated then consider using an epoxy grout.

Low absorbency tiles should be selected, ideally less than 0.5% absorption. Absorbent surfaces should be allowed to dry and then primed with UltraTileFix ProPrimer. Dilute the primer 1 part to 3 parts water and then allow to dry. Tiles should be fixed using a highly modified cementitious adhesive, in accordance with EN 12004 – capable of withstanding continual immersion. UltraTileFix recommend ProFlex SP, ProFlex SPES or ProFlex S2. It is critical that a full bed adhesion without any voids is created and to ensure this, a minimum 3mm bed depth is recommended.

There will be a requirement for movement joints (please see BS 5385) which should be considered before tiling commences. A suitable sealant should be selected and used on all wall and floor junctions at least.

Tiling onto floors using an uncoupling system

A – Load bearing substrate
B – Prime
C – Adhesive
D – Uncoupling membrane
E – Apply adhesive (flexible only should be used)
F – Install tiles
G – Grout all joints

Uncoupling systems are an excellent method of fixing tiles in very testing environments. The science behind uncoupling can be summarised as: “A system used to isolate the finished tiled floor from the subfloor to prevent damage from lateral movement, subfloor cracking and water penetration.” Systems generally involve the use of a profiled polyurethane mat with a fleece underside which is bonded to the substrate using a flexible adhesive. Tiles are then bonded to the mat using a flexible tile adhesive and grout. For full information on how these systems work and the installation methods required, please refer to the manufacturer’s instructions. However, the following general criteria should always be met:

  1. The substrate must be even, rigid and load bearing.
  2. Boarded floors (timber or backer boards) must be screwed down as per instruction, and replace any boards that are damaged. Uncoupling mats will accommodate lateral movement, but are not designed to withstand vertical movement, so subfloors must be braced to make them sound and strong. All timber floors must have adequate under floor ventilation to prevent the timber from moving, post installation, due to humidity changes.
  3. Tile selection should be made on the basis of the likely load that the flooring will be subjected to i.e. thickness and strength in accordance with end use expectations.
  4. Prime the subfloor, if required, with UltraTileFix ProPrimer.
  5. The anchoring fleece should be bonded using adhesive. The adhesive must bond to the substrate and mechanically anchor the fleece to the underside of the mat. We would recommend using a 4mm notched trowel with flexible adhesive.
  6. Once the mat is secure the tiles can be fixed using an UltraTileFix flexible adhesive. It is advised that the cavities in the matting are first filled with adhesive using a smooth edge towel before finally applying with a notched towel to achieve the bed thickness required.
  7. Grouting should be carried out using UltraTileFix ProGrout Flexible.

Tiling onto calcium sulphate screeds

Flowable calcium sulphate screeds, also known as anhydrite, hemi-hydrite and gypsum, have many advantages over traditional sand/cement screeds such as:

  • Can be laid thinner, reducing loadings
  • Can be manufactured using industrial by-products so an environmentally friendly alternative
  • Increased speed of installation as they can be pumped

It is important that calcium sulphate screeds are identified before any tiling installations are carried out because they have different requirements. They may not be visually different from traditional screeds so always enquire, particularly if the screed contains underfloor heating. We recommend the use of a barrier primer on
calcium sulphate screeds to avoid migration of moisture between adhesive and subfloor.

Unlike sand / cement and cementitious products, which can still have extremely high tensile and compressive strength whilst retaining a high level of moisture, calcium sulphate screeds need to reach a level of dryness to enable them to perform correctly underneath the tiling. The approved standard moisture test method is to use a surface hygrometer. This is an insulated box, fixed to the unheated floor for typically 4 days, after which the moisture in the air trapped in the box reaches equilibrium. This air is then tested using either an analogue or digital hygrometer. If the reading is less than 75%RH (relative humidity) then the screed is dry enough.

Other indicative test methods may be used to help identify if moisture is a concern or if the screed is close to dry. A simple test is to tape a piece of plastic to the floor for 48 hours. Moisture condensing on the underside of the plastic or a darkening of the screed indicates moisture levels are still significant.

The recommended drying times of calcium sulphate screeds, as quoted by the manufacturers, are usually based on drying conditions at 20°C, low air humidity and an open surface with no materials overlaid.

This does not represent a typical site scenario so they should not be relied upon. It is also important to remember that underfloor heating must have been fully commissioned. This does not mean a simple air pressure test but means a full cycle through the heating range. This is necessary to:

A. Identify if any weaknesses are in the screed by showing likely points of cracking and spalling (typically due to poor installation of the screed with heating)

B. Assist the drying of the screed

Preparation
1. Once the above criteria has been met the screed is ready to receive this. To ensure consistency it is advisable that all screeds are mechanically prepared using a rotary disc to remove any laitance and weak upper surface (consult the screed manufacturer for their specific requirements). The screed must also then be made dust free.

2. Ensure that the calcium sulphate screed is fully dry (less than 75% humidity).  If in doubt then the supplier or installer of the screed must be contacted to confirm that the drying period has been observed and gain their assurance that the screed is dry.  The manufacturer of the screed will know better than anyone how long their screed will take to dry out at certain depths.

3. In general calcium sulphate screeds take 1mm/day for the first 40mm to dry out and a further 0.5mm a day for anything thicker, so a 50mm screed will need a minimum of 60 days before being anywhere near dry.  80mm would be as long as 40 days plus a further 80 days giving 120 days minimum.  Calcium sulphate can be force dried, but check with the manufacturer/installer of the screed on how to do this.

Priming
We recommend applying 2 coats of primer, ensuring consolidation and isolation of the calcium sulphate. This allows the standard classified cementitious tile adhesives to be utilised in the normal manner.

Coat 1
4. Prime the floor with a coat of UltraTileFix ProPrimer. The primer should be diluted with 3 parts water and thoroughly scrubbed into the floor. Apply thinly and do not leave pools or puddles of primer. Leave to dry thoroughly, typically overnight.

Coat 2
4A.  UltraTileFix ProPrimer should be diluted with 1 part water to 1 part primer. Brush or roller onto the floor applying thinly, avoiding pooling. Allow to dry to a tacky clear film, typically 4 – 6 hours.

5. If underfloor heating is present there should be expansion strips between the different heating zone areas to enable the screed to move independently, around any perimeters, and at upstands and door thresholds. In all cases these strips should not be tiled over but should be carried through to the upper tiled floor, using a silicone sealant or similar to enable a continuous floor to be achieved. When underfloor heating is present we advise that a polymer modified adhesive is used. It is always beneficial to use a rapid set product on these screeds to minimise the migration of moisture between screed and adhesive during curing.

Tile Types

The range of tiles available today is almost endless, and will continue to develop. Below is a summary of the most common types and a description of their properties and make up. Those most traditionally used are manufactured from raw materials to create a ’tile’ with a variety of performance and decorative characteristics.

Tile Types

Ceramic: A tile consisting of mixtures of clay, which are pressed and kiln fired at high temperatures, to give a hard ‘bisque or biscuit’. The ‘biscuit’ has a relatively high degree of absorbency enabling the adhesive to bond fairly easily. Ceramics may be left unglazed but are more often glazed to give more decorative options as well as physical benefits. This includes terracotta and quarry tiles. Ceramic tiles are generally not considered suitable for external use.

Vitrious (fully vitrified and semi-vitrified): Similar in manufacture to ceramic tiles, but incorporating different clays to provide tiles that are harder, denser and less absorbent. They may be fired for longer and at higher temperatures than ceramics. The term vitreous simply means ‘glass like’. The classifications for ‘fully vitrified’ is a tile with less than 3% water absorption. Fully vitrified tiles require the use of a polymer modified adhesive may be used externally in areas for spas and swimming pools. Semi-vitreous tiles have a water absorption between 3-7%.

Porcelain: Porcelain tiles are made from a different blend of clay, and a manufacturing process similar to ceramics. This controls shrinkage and water use and results in a very dense, hard-wearing tile with an absorbency of less than 0.5%, suitable externally for commercial projects as well as for swimming pools and areas subject to frost. ‘Full bodied’ porcelain doesn’t show wear as there is no upper glaze. They are much more affordable and are nowadays also used in domestic installations.

Terrazzo: Either pre-manufactured or laid in-situ, terrazzo consists of granite and marble chips in a Portland cement, or sometimes epoxy resin binder. They can be polished to give a low absorbent and high strength tile suitable for commercial use.

Agglomerate (quartz): This type of tile is manufactured by mixing graded pieces of granite and marble with cement and resins to give a pre-formed tile. They generally have low absorption.  These tiles are sometimes referred to as quartz.  For use of these type of tiles with underfloor heating always consult the manufacturer for guidance.

Glass: Manufactured from glass, and available in many striking opaque colours. Traditionally manufactured in small sizes and often on mosaic backings, they are now available in much larger formats. They are very hard and offer extremely low porosity. There are presently no British or European standards covering glass tiles so it is always worthwhile contacting the manufacturer for adhesive recommendations. Typically a minimum of a C2 classification is required but some decorative tiles may require resin based adhesives.

Natural Stones

There is a wide variety of natural stones available today; all are cut from larger stones to make varied sizes and shapes with a host of characteristics. Always check with the supplier regarding a sealing product for use before and after grouting.  Special care should be taken when dealing with resin backed stone.

Travertine: A form of limestone, travertine is very popular. It is a porous material and can be supplied with a good surface texture but can also be filled or honed to provide a smooth surface. Travertine should always be sealed before grouting. It is recommended to use a rapid set adhesive to minimise water absorption and potential staining.

Limestone: Available in a coarse or fine texture, and of varying strength, it is a porous material and should be sealed prior to grouting. It is recommended that a rapid set adhesive is used to minimise water absorption and potential staining.

Marble: Very durable and strong, available in a vast array of colours, due to impurities when being formed. Stronger than limestone and travertine, it is often supplied polished and sometimes cut down for mosaics. Although not as porous as limestone and travertine it is still recommended to seal prior to grouting.

Granite: Very strong stone suitable for heavy wear situations, that is resistant to most domestic use acids. It is porous and requires sealing before grouting. We recommend that a rapid set adhesive is used.

Slate: Very durable natural stone found in slabs that are split and then cut to size. Very hardwearing and offers a textured surface with a degree of anti-slip, making it ideal for external use. Slate, often supplied un-calibrated, should be sealed before grouting.

Tile Dimensions

The dimensions of any tile can play an important part in selecting the correct adhesive for use. Smaller tiles are generally easier to fix. The following common descriptions are used for different tile dimensions.

Mosaic: Typically glass or marble of small dimensions (less than 50mm x 50mm) mounted onto backing paper. Supplied in 300mm x 300mm sheets, they can be cut down to smaller bands, enabling feature strips to be created. Generally mosaics do not require special adhesives but extended set products may be beneficial to allow a longer working time for intricate designs.

Large format: There is no official definition for the dimensions of a tile classed as large format. For the purpose of this guide, any tile that has a perimeter measurement in excess of 1.6m is classed as large format i.e. 400mm x 400mm or 600mm x 200mm. Large format tiles require the use of higher strength polymer modified adhesives with improved slip and slump characteristics.

Uncalibrated: This is a term used for natural stone tiles that are not cut to give tiles of the same thickness. Unlike manufactured tiles, un-calibrated tiles will require an adhesive capable of being used at thicker bed depths to ensure a consistent finished surface level is achieved.

Substrate Preparation

The suitability of a substrate should always be fully assessed before carrying out any tiling.

The main criteria to be assessed is:

  • Is the substrate strong and stable?
  • Has the substrate dried/cured completely?
  • Is the substrate smooth and reasonably level?
  • Is the substrate porous or non-porous?  A test area should be used.

If the answer to any of these is ‘no’, then the substrate is not suitable to be tiled onto and further preparation is required before priming and fixing.

Why should you prime?

Priming of substrates is key to ensuring the selected adhesive can perform to its optimum. There are three basic reasons why priming is important. UltraTileFix provides the perfect solutions.

  1. The sealing of substrates to reduce moisture absorption from cementitious adhesives enabling them to hydrate and cure properly. We recommend the use UltraTileFix ProPrimer.
  2. On dense and impervious substrates it is beneficial to utilise a bonding primer to enhance the adhesion of the tile to the substrate. Such substrates would include epoxy damp proof membranes, tile on tile, asphalt and painted surfaces. For this we recommend the use of UltraTileFix ProPrimer neat.
  3. On some substrates it may be necessary to create a barrier between the substrate and adhesive to ensure compatibility. This may be when applying cement adhesive to calcium sulphates or when bonding onto substrates affected by high alkali adhesives. We recommend that UltraTileFix ProPrimer is used when a barrier primer is required.

Is the substrate porous or non-porous?

General priming guidance is to use UltraTileFix ProPrimer when tiling onto a porous substrate such as sand/cement. Whereas UltraTileFix ProPrimer neat should be used on non-porous substrates such as ceramic, terrazzo, asphalt and epoxy based damp proof membranes. We do not recommend the use of PVA for priming and have produced an article to explain this.

Read: PVA for Priming – Good Practice or Bad Habit.

For underfloor heating systems in terms of priming please see specific advice guides.

 

 

Movement joints in a tiling installation

The inclusion of movement joints in a tiling installation is something that should be incorporated at the design stage by the specifier or architect. However, it is beneficial to have a basic understanding of where, when and why movements joints should be used.

Background to movement joints

Regardless of the type of tile being used, they must all be considered as ‘solid’ materials with very little dimensional change despite conditions. Building movement may occur due to changes in conditions, physical movement due to size, settling or drying out of the building, weight loading, level of trafficking, thermal changes or simply due to the construction design itself. Floor construction in particular needs careful consideration as the functionality of a floor is such that its stability and integrity must be maintained to enable the building to be utilised.

Walls

All junctions between walls and floors should have a movement joint included. However, walls themselves are under continual stress and have the potential for movement, so consideration of movement joints should be move. Consider the use of a movement joint in all of the following areas:

  • They must be incorporated where there are any existing movement joints within the wall structure. They should be aligned directly over the existing structure joint and be at least as wide.
  • At internal corners between walls to relieve stress under thermal, vibration or any other movement. This includes where internal walls meet ceilings; a suitable silicone sealant may be used.
  • Where the wall tiling meets a different substrate – the tiles should be left short and a movement joint utilised. A suitable silicone sealant should be used.
  • Where tiling bridges are used across different substrates a movement joint should be created at the junction.
  • On large walls movement joints should be included both horizontally and vertically. Subject to the building design, the joints may need to be incorporated anywhere between 3m and 10m.
  • External wall joints (close to external angles) and all internal angels. The inclusion of a movement joint will prevent fracture and bulging of tiles with building, thermal and/or vibration movement.
  • Movement joints must be incorporated at more frequent positions, should the walls be subject to significant thermal or vibration movement.

Movement joints can be incorporated in to the design to minimise aesthetic concerns.

Floors

Including movement joints in floors enables the tile bed to move in unison with the individual substrates. Selection of movement joint type will depend on joint width requirement, finished floor use and movement capability. The range of materials available and their typical area of use include; aluminium for general commercial installation, brass and stainless steel for heavy commercial and factory use, and PVC for most other applications. Always consult with the manufacturer as to the most suitable joint for your application. Consideration to the use of a tiling movement joint must be given in all of the following areas:

  • They must be incorporated and aligned with any movement joints within the floor’s construction. The joints should be continued through the entire depth of the tiles and adhesive.
  • At specified distances across a floor to create individual tile beds (general consensus is that movement joints should be utilised at distances between 5m and 8m).
  • Floors with underfloor heating systems should incorporate movement joints with a limited bay size of a maximum of 25m².
  • At day joints or stress induced saw cuts in subfloors. The level of movement at these joints is often unknown and is usually dependant on the age of the building and whether the subfloor is fully dry. If in doubt, incorporate a movement joint.
  • All perimeters and any fixed features which interrupt the floor, such as pillars or aisles, should have an allowance for movement. Sometimes this can be a suitable silicone sealant, of if underneath skirting it may simply be a gap. In areas of high thermal change, such as conservatories this is extremely important.
  • Movement joints should be included between any underfloor heating zones to enable each to perform independently.
  • Movement joints should be placed directly above any supporting walls or structural beams as they will add rigidity to the floor. The remaining floor area may be prone to a degree of flex or vibration.
  • Junctions between floors and walls.

Movement joints can often be incorporated into the floor design to minimise aesthetic concerns whilst ensuring integrity of the tiled floor.

Grouting Tips

The finished look of a tiling installation is down to the design and the tiles selected. There are, however, a significant number of grout lines also visible which can affect the final appearance. It is therefore important to grout carefully, getting the best result possible. Here are some tips to follow:

  • Mix the grout in accordance with the manufacturer’s instructions. It is particularly important not to make the grout too fluid as this will cause separation, resulting in a weaker surface of varying colour.
  • When mechanically mixing grouts a drill speed of less than 300RPM with the paddle held beneath the grout surface is ideal. Aggressive mixing can pull air into the product which can show as air holes upon curing.
  • Be patient and leave the grout to stand for a couple of minutes after mixing, allowing the reaction of all the components to begin. A quick stir after a couple of minutes standing is also advised.
  • Do not re-mix the grout after this initial period, and do not add extra water to try and retain mobility. If the grout has thickened up too much to apply then discard it.
  • Once in the joint, the grout should be left to firm before cleaning down. This is to ensure it remains in the joint and does not absorb significant levels of moisture when the area is cleaned.

NB: The time to firm is dependent on many parameters. The more porous a tile and/or substrate then the quicker the firming up will happen i.e. ceramic tiles will be able to be cleaned much earlier than porcelain tiles. Joint width will also play a part, with wider joints taking longer to firm. Finally, ambient conditions will have an effect. Cold and damp environments with poor ventilation will result in the grout taking longer to firm.

  • When cleaning do not over apply water. We advise using a sponge or squeegee. If using a ‘washboy’ it is important to drain the sponge thoroughly otherwise this can reintroduce a significant amount of water into the grout, causing separation and surface patchiness when curing.

Floor Tiling – Asphalt

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTileFix ProLevel One, UltraTileFix ProLevel Two and UltraTileFix ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTileFix Technical Department.

Asphalt

A – Flooring grade asphalt substrate
B – Prime using UltraTileFix ProPrimer neat
C – Apply adhesive (selected upon tile type)
D – Install tiles
E – Grout all joints

Instructions:
Used on floors and roofs due to its ability to prevent moisture passing through. It varies in strength and flexibility depending on the desired end use. Flooring grade asphalt is the only material suitable for tiling onto. Do not lay onto roofing grade asphalt. It should be a minimum of 15mm thick throughout the entire area. The surface should be crack free. Newly laid asphalt must be fully degreased to ensure surface bloom does not hinder adhesion. The asphalt must be primed to enhance adhesion. The use of a flexible adhesive and grout is recommended.

Floor Tiling – Timber/Wood

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTileFix ProLevel One, UltraTileFix ProLevel Two and UltraTileFix ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTileFix Technical Department.

Plywood Overlay

08_PlywoodOverlay

A – Floorboards
B – Plywood overlay
C – Prime (remembering to use UltraTileFix ProPrimer neat if marine grade is used)
D – Apply adhesive (flexible only should be used)
E – Install tiles
F – Grout all joints

Backer board

09_TileBackerBoard

A – Floorboards
B – Adhesive
C – Backer board
D – Apply adhesive (flexible only should be used)
E – Install tiles
F – Grout all joints

Instructions:
Unlike sand/cement screed and concrete, which are inherently strong and stable without any vibration or movement, there are different considerations to be made with timber/wooden subfloors. Existing timber/wooden floors must be strong, rigid, stable and capable of withstanding the load of adhesive and tiles. They should be sufficiently supported to prevent flexing. Additional noggins may be required to stabilise the floor. Timber/wood is prone to movement under varying levels of humidity so adequate ventilation beneath is necessary.  Identify if plywood is porous or non-porous prior to priming.

There are 2 options to enable tiling to be carried out on timber/wooden subfloors:

  1. The existing timber/wooden subfloor should be overlaid using exterior or Class 3 plywood of a minimum thickness of 15mm. All cut edges and the underside of the plywood should be sealed prior to fixing. The plywood must be screwed, not nailed, at 300mm centres.
  2. Option 2 is to overlay timber/wooden subfloors using a proprietary tile backer board. The backer board must be a floor grade product.

Follow the manufacturer’s guidelines regarding fixing it to the floor. This may include both mechanical fixing with screws and bonding with adhesive.

Regardless of which option above is selected we always advise to use a flexible adhesive and grout when installing on timber/wooden subfloors. They need not be problematic if the correct approach is carried out. If in doubt contact the UltraTileFix Technical Department.

Floor Tiling – Tiled

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTileFix ProLevel One, UltraTileFix ProLevel Two and UltraTileFix ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTileFix Technical Department.

Tiled

A – Concrete substrate
B – Existing tiles
C – Prime using UltraTileFix ProPrimer neat
D – Apply adhesive (selected upon tile type)
E – Install tiles
F – Grout all joints

Instructions:
The subfloor should be assessed to ensure that all tiles are fully bonded. A mechanical abrasion of the tiles will clean and prepare the surface, whilst also helping to enhance adhesion. All tiles should be degreased and allowed to dry before proceeding. We recommend priming the tiles using a bonding primer.

Hard vinyl tiles
Instructions:

Not all vinyl tile flooring is suitable to be tiled over. Cushioned or flexible vinyl tiles should not be overlaid and must be removed along with the adhesive residue. Hard vinyl tiles should be lightly abraded (see NB below) and then primed with UltraTileFix ProPrimer neat (bonding primer).

NB:
Old ‘crunchy’ tiles should not be abraded as they may have been manufactured using asbestos fibres. Such tiles are typically 225mm (9 inches) square tiles and are often bonded onto a black adhesive. The use of an uncoupling membrane is advisable in such circumstances.

Floor Tiling – Concrete

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTileFix ProLevel One, UltraTileFix ProLevel Two and UltraTileFix ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTileFix Technical Department.

Concrete

Instructions:
Concrete varies significantly in its finish, from tamped to power-floated. In all cases, the concrete must be fully cured and have been left to dry. For power-floated concrete it may be necessary to remove surface additives and hardeners by mechanical abrasion. Power-floated concrete should be considered a non-porous surface. Fully dry concrete surfaces can be improved with the application of an UltraTileFix levelling compound. Before commencing the tiling process the substrate should be confirmed dry. If in doubt, a moisture reading should be taken to confirm.

Priming:
Tamped concrete – apply 1 coat of UltraTileFix ProPrimer (diluted 3 parts water to 1 part primer). Power-floated concrete – apply 1 neat coat of UltraTileFix ProPrimer. Allow the primer coat to dry before continuing.

Floor Tiling – Sand/cement screed

The main consideration for laying floor tiles is the fact that once in use, they are not just decorative and hygienic but also functional. They will have to perform under daily trafficking, whether this is foot traffic in a domestic installation or heavy wear and tear in a commercial application.

It is therefore critical that full attention to correct preparation and application is paid.

With wall tiling there is not always a need for a full bed bond, but with floor tiles it is essential. The strength build-up of the adhesive is far more important too as the tiles need to be walked upon to grout, and in most cases, the floor needs to get back into service. To enable this we advise the use of powder products rather than ready mixed adhesives.

To ensure full bonding, the substrate should be as even and level as possible. In most cases, rough floors or floors with height variations can be prepared using UltraTileFix ProLevel One, UltraTileFix ProLevel Two and UltraTileFix ProLevel Fibre.

All offer extremely goof flow, and a floor level classified as SR2 can easily be achieved (no greater than a 5mm deflection under a 3m straight edge).

With skill an SR1 floor can be achieved (3mm deflection under a 3m straight edge). For more information on these products please contact the UltraTileFix Technical Department.

Sand/cement screed

A – Sand/cement screed or concrete floor
B – Prime: if the screed is rough or uneven prepare it using an application of an UltraTileFix levelling compound following by another primer coat
C – Apply adhesive (selected upon tile type)
D – Install tiles
E – Grout all joints

Instructions:
The screed must have cured and dried under good ambient conditions. Any cracks should be repaired with a rapid repair mortar. Any weak or friable screed should be removed and repaired. Movement joints should not be covered with tiles as they are designed to allow for subfloor movement. Follow joints through to the tile surface and use an appropriate expansion material or cover strip. Fully dry rough or uneven screeds can be improved with an application of an UltraFloor levelling compound. Before commencing the tiling process the substrate should be confirmed dry. If in doubt, a moisture reading should be taken to confirm.

Common Tiling Terms

There is a great deal of terminology used within the tiling industry. The following is a collection of the most common terms and their meanings.

Additive: Generally refers to a liquid polymer that can be added to a grout or adhesive to improve its adhesion and flexibility.

Adjusting time: The length of time after fixing a tile that it can still be adjusted without detriment to the adhesive bond strength.

Buttering: The process of spreading a thin layer of adhesive of the underside of textured tiles directly before bedding. This is to ensure a full bed of adhesive is achieved.

Calibrated / Un-Calibrated: A reference to the thickness of tiles. Calibrated tiles are manufactured to give a uniform depth so can be bedded onto adhesive using the same bed depth. Un-calibrated tiles are typically natural stone of varying thicknesses and require thicker bed depths.

Efflorescence: The appearance of light deposits of salts on cementitious materials, occasionally visible in grout lines. It is as a result of moisture bringing salts to the surface that when dry leave a white powdery deposit showing light and dark variations within the grout. It can occur due to moisture migration from the background substrate, by watering or premature cleaning off of the grout. It is not detrimental to grout performance.

Finished walls and floors: Prior to any tiling it is important that walls and floors are finished providing the level of smoothness and regularity required. This may be by means of rendering or plastering on walls or by use of a suitable smoothing compound on floors. A wall classed as finished and ready for tiling will have no greater than a 2mm deviation under a 2m straight edge. A finished floor, a 3mm deviation under a 3mm straight edge.

Fixing time: The length of time, after applying an adhesive, that tiles can be fixed.

Frost-resistant: The ability of a tile, adhesive or grout to perform even when the external conditions can result in frost formation. The tiles usually have to have very low water absorption to ensure cracking does not occur.

Grout after: Period after which the tiles are firmly set into the adhesive and will allow grouting to begin without disturbing the bond of the tile.

Internal / external: Products that are suitable for both internal and external use without affecting their performance parameters.

Laitance: A term used to describe a fine particle material deposit (often referred to as ‘fines’ or ‘fat’) found on the surface of cementitious or calcium sulphate subfloors. The deposit is a weak interface and should be removed to ensure the tile adhesive has a sound, strong surface to bond to. Laitance should be mechanically removed (often followed by vacuuming), and is caused by too much water when installing a screed. It can also be found when a levelling compound has been incorrectly used.

Movement joints: Gaps left in tiled floor designs and filled with a flexible material to enable the substrates and/or building to move independently of the tiling. Typically between different substrates, where tiles abut uprights, at corners and where expansion joints are present in the existing floor. Movement joints are essential design features.

Mould resistant: The ability of a product, usually a grout, to resistant the growth of mould.

Open time: The time, usually in minutes, after application of an adhesive within which it will still bond and secure the tile. This can be influenced by the nature of the substrate (with absorbent substrates reducing open time) and also the ambient conditions where warm, dry conditions reduce the open time.

Polymer modified: This term refers to adhesive and grout formulations that include added polymer for increased adhesion and flexibility. Polymer modified products are common due to the increased use of vitrified and porcelain tiles, which have a low absorbency and require a ‘better’ adhesive to adhere them.

Pot life: The length of time after mixing a grout or adhesive that you have to use it. After the pot life has been reached, the mixing product should be discarded. Water should not be added to try and regain its characteristics.

Primer: A liquid applied to a substrate prior to tiling. Used either to enhance adhesion or to reduce porosity providing a longer open time for the adhesive.

Rapid setting: An adhesive modified so it sets rapidly, by utilising different cements and technologies. Enables tiling and grouting to be carried out in a shorter time frame.

Ready mixed: Adhesives that are supplied ready for use, without the requirement to add any water or liquid polymer. Usually acrylic based and generally only used for wall tile installations where set time is not so critical.

Hard/Set time or ‘Workability’: The time, usually in hours, after which a bonded tile can be grouted and/or walked upon without affecting the bond. The set time for ready mixed adhesives is greatly dependent on the type of tiles and substrate.

Slump of slip: The vertical movement of a wall tile after it has been bedded into an adhesive. Traditionally battens have been used to prevent slump but modern adhesives are modified with anti-slump or anti-slip characteristics.

Solid bed fixing: A term used to describe a bed of adhesive or greater than 95% contact between tile back and adhesive, and between adhesive and substrate. This is recommended on all floor and large format wall installations.

Tanking: Applying a liquid waterproof membrane, usually incorporating a mesh, in areas such as showers to protect moisture sensitive background substrates from water impregnation.

Tensile adhesion strength: A standard test used to determine adhesion strength of tiles and adhesive. Usually quoted in N/mm² and the higher the number the greater the bond between the materials.

Tile after: This is the time after which the tiling process can start. Depending on the type of application being used, priming is generally the first stage.

Tile backer boards: These boards can be constructed from a variety of materials including cement, insulation or resin based compounds reinforced to give added strength. These boards usually offer waterproofing and/or insulation properties.

Uncoupling membranes: These are membranes used below new tiling installations and generally fixed direct to the floor screed for the purpose of preventing known problems in the subfloor effecting the new tiling installation.  By creating a separation layer between the tiles and the screed can effectively overcome substrate movement tensions, and stress crack issues.  They can also be used to provide waterproof protection neutralising vapour pressure build up in problematic, as well as damp screeds.  They can be used above underfloor heating systems.

Underfloor heating: There are two basic types of underfloor heating systems.  The first uses warm water pipes either encased within the floor screed or fixed into pre-formed insulation panels.  Once positioned, installed and commissioned the floor covering can be installed.  Hot water piped through the system provides the heating.  The second system uses electrical heating mats placed on to the prepared floor and connected to wall mounted thermostatic controls.  Once commissioned the floor covering is installed.

Waterproof: The ability of an adhesive or grout to prevent the passage of water. Normally epoxy or resin materials, which are often also chemically resistant.

Water repellent: Used usually when referring to grout, it’s the ability of the product to repel water from its surface. Does not imply a waterproof grout.

Water resistant: The ability of an adhesive or grout to still retain its performance even when subject to fill immersion in water.

Water staining: A situation where moisture from adhesives and grouts gets into natural stone and dissolves existing materials resulting in discolouration. usually of the edges, but sometimes the faces of the tile. The use of rapid set products minimises this risk, as does dealing of tiles prior to grouting.

Working time or ‘Workability’: The time, usually in minutes, after mixing an adhesive or grout that will still retain its characteristics to enable it to be applied, bedded onto and finished. With rapid set products the working time will be reduced the longer the material is left in the mixed container. Also, warmer temperatures will reduce the working time.