THE TILE ASSOCIATION

Transcription

1 Published by THE TILE ASSOCIATION The Tile Association Forum Court, 83 Copers Cope Road, Beckenham, Kent BR3 1NR Tel Fax E info@tiles.org.uk W

2 1. FOREWORD This paper has been prepared by a Technical Working Group of The Tile Association. The paper has been written with the aim of providing advice for all parties involved in the use of resin agglomerated tile and should be used in conjunction with current and forthcoming British, European and International Standards. The Tile Association acknowledges the support given by members of the Working Group and BASA in the drafting of this document. 2 HISTORY AND SCOPE As part of its services, The Tile Association offers an independent inspection service. A number of inspections have highlighted failures associated with the use of resin agglomerated tiles which has led to the drafting of this document. British Standard BS5385 5:2009 clause 11.1 states Agglomerated stone products are manufactured from hydraulic cement, resin or a mixture of both, combined with stone and other aggregates. British Standard BS EN is the Standard that determines the classification of agglomerated stone. Details of other Standards are listed in the bibliography. This document sets out to provide advice on considerations to be given to the physical characteristics of resin agglomerated tiles, the substrate, fixing, cleaning and maintenance of resin agglomerated tiles on internal walls and floors. 3. PHYSICAL CHARACTERISTICS OF RESIN AGGLOMERATED TILES 3.1 Production Generally, three types of resin agglomerated floor tiles are available, these are: marble granite quartz Marble and granite are used to manufacture blocks, which comprise a mix of 95% selected and dried raw materials and 5% polyester resins (this will vary depending on the manufacturer, some manufacturers use a higher percentage of resin, which can affect the performance of the floor tiles. A higher percentage of resin will Page 2

3 increase the coefficient of thermal expansion and reduce abrasion resistance). These materials are vibro compressed under vacuum and allowed to stand while the resin generates heat to set the block within two days. The blocks are stored for a further seven days and then cut into slabs to produce 12mm, 20mm and 30mm slabs. Individual slabs can also be manufactured using quartz and granite, using the same selection and mixing of raw materials and resins, but pressed between two paper sheets as individual slabs and cured in a curing chamber at C for approximately one hour, then allowed to cool and then finished to meet client requirements. 3.2 Sizes Slabs vary in size between different manufacturers; slabs produced from blocks are generally 3050 x 1250mm, whereas quartz slabs are generally larger because of the kitchen worktop market. Tile sizes, as with all products, are generally available in large and small formats. Examples of these are: 1200 x 1200mm 1200 x 600mm 600 x 600mm 600 x 300mm 400 x 400mm 300 x 300mm Other sizes can be cut upon request. Generally skirtings are available to match with a finished top edge Resin agglomerated tiles are normally available in thicknesses between 10mm 12mm. They are also available in greater thicknesses for heavy duty conditions. Since the materials are cut from slabs the dimensional accuracy is generally high and in accordance with BS EN Finishes and edge details The standard surface finishes are: polished honed sand blasted Page 3

4 The edges are typically finished either square or bevelled to suit the designer s requirement. The square edged tile will resemble a natural stone tile. A bevelled edge will give a more recessed joint. Because of the need to meet HSE requirements for Slip Resistance (ref: Safer Surfaces to Walk On, CIRIA C652/2010) the manufacturers have been continually developing new surfaces to increase the SRV (Slip Resistance Value) for Pendulum Testing and a range of alternative finishes is available to suit most situations. (See clause 4.1.2) 3.4 Characteristics/performance Because the products consist predominantly of natural materials, they have performance characteristics similar to natural stone. Granite and quartz agglomerated tiles are harder wearing than those made with marble. The particular performance and suitability in locations should be confirmed with the manufacturer. Granite and quartz agglomerated tiles are more resistant to acidic chemicals than marble agglomerated composite tiles. 3.5 Moisture sensitivity Resin agglomerated tiles may show varying degrees of moisture sensitivity and this characteristic is exhibited by curling caused by differential expansion. For this reason, it is essential that any cementitious floor screeds to receive resin agglomerated tiles should be completely cured and tested to ensure that they have a moisture content of not more than 2% by weight or 75% relative humidity using the appropriate test equipment and also that an appropriate adhesive is chosen. See clause 4.3 Resin agglomerated tiles are not recommended for use in external areas or swimming pools or any other water retaining structures, e.g. spa baths or fountains. Resin agglomerated tiles can be used externally on facades by utilising mechanical fixing. 3.6 Thermal movement Generally, agglomerated tiles will have a higher coefficient of thermal expansion than porcelain or natural stone. This is reflected in the recommendations for frequency of movement joints and guidance in British Standard BS5385 5:2009 clause 4.4. Page 4

5 Table 1 Typical coefficient of thermal expansion of hard construction flooring products This table of the coefficient of thermal expansion (C.T.E.) illustrates the typical thermal movement of resin agglomerated stone tiles compared to other materials. Type of Hard Flooring C.T.E x 10 6 o C 1 Comparison with Concrete Concrete 10 Sand:cement screeds 9 10 Medium Group Blb dust pressed 5 to 9 Medium tiles Group Bla dust pressed 6 to 7 Medium tiles Resin agglomerated stone tiles* 7 to 38 Can be very high, greater than most bases Granite & Basalt 6 to 9 Medium Marble 3.5 to 7 Low to medium Limestone & Dolomite 6 to 10 Medium Sandstone 11 to 12 Medium Quartzite 11 to 13 Medium Glass tiles & mosaics 7 9 Medium Terrazzo 7 to 13 Medium Slate 3 to 9 Low to medium *These are general values, Check with the manufacturer for further information about specific products 3.7 Abrasion resistance The abrasion resistance for all resin agglomerated stone products reflects their natural stone components. Marble agglomerated tiles have a lower abrasion resistance than quartz or granite agglomerated tiles but may still be suitable in heavily trafficked areas. Consult the tile manufacturer for guidance. Polished products are more likely to show scratch marks. 3.8 Transportation and storage of product Smaller size products are supplied in boxes and the larger size in crates. Resin agglomerated stone tiles should be protected from water during transportation. Resin agglomerate tiles should not be stored externally unless they are completely protected from direct sunlight, water, rain and frost. Deliveries should be coordinated so that the materials can be stored correctly. Page 5

6 Materials should remain in their purchased packaging for as long as possible. They should be stored flat and not leant against walls. The tiles should be acclimatised. See Clause 5 4. DESIGN CONSIDERATIONS 4.1 Tile selection It is important to consider the physical characteristics of resin agglomerated tiles and the service conditions of the tiling project before any design decisions are made. Resin agglomerated tiles are normally available in thicknesses between 10mm 12mm. They are also available in greater thicknesses for heavy duty conditions. The surface finish should be considered with regard to slip resistance, traffic conditions, spillage and maintenance. Because both tiles and slabs are produced from the same materials it facilitates the design decision on surfaces such as steps and risers, worktops etc Appearance There is a wide choice of colour availability because of the extensive range of coloured aggregate fillers. Because it is a manufactured product it can be altered to include reflective fillers and other features. Resin agglomerated tiles are usually supplied polished, honed or sand blasted. Polished finishes are generally used where a reflective surface is required and slip resistance is less important. A honed finish tile is chosen for its matt appearance where a reflection is not required and has improved slip resistance. A sand blasted finish is used when a higher slip resistance is required e.g. intermittent wet locations. Surface texture will affect the cleaning regime required. When considering choice of texture it is important to understand there is a compromise between slip resistance and ease of cleaning and/or maintenance. Page 6

7 4.1.2 Service conditions Resin agglomerated tiles have different properties from natural stone and ceramic materials and these differences should be taken into account at the design stage. For example: slip traffic conditions thermal conditions intermittently wet locations submersed locations Slip Materials to provide safe surfaces for walking is something which is continually evolving with manufacturers developing new finishes to cope with the demands of buildings and their design. One of the most informative documents on this subject is the CIRIA C652, produced in collaboration with all sectors of the building industry. This document provides some interesting guidelines, but one of the main features is the Slip Assessment Tool (SAT), which can be found on the HSE website This enables the designer or owner of a building to undertake a Risk Assessment on the building and areas of concern, so as to establish the element of risk which they are prepared to accept and then to select a material with a Slip Resistance Value to match that risk. The table, as printed in the CIRIA document, is shown below: Risk 1 in: Minimum SRV (see also Section 4.2.2) Low Medium Medium Medium 20, i.e. 5 per cent 24 High Qualitative categories (from Table 3.1) BRE qualifies this data by indicating that it was obtained from a small sample size, using fit persons at a moderate walking pace. The figures relate to a normal walking situation with no pushing or pulling or turning tight corners, and utilising a horizontal surface. If these conditions are not met, the required SRV for the same risk of slipping will be higher. Note that the SRV values given in Table 4.2 are installed figures. To compensate for degradation of SRV during installation and a Page 7

8 high density of wear, some specifiers stipulate an increased figure. (CIRIA Document) The method which is adopted to obtain the Slip Resistance Values of floors is the Pendulum Method, which measures the coefficient of friction of the tile surface. It is important to note that the requirement for stone and porcelain is different; The UK Slip Resistance Group recommend the use of a 4S slider for porcelain and a TRL soft rubber slider for stone. This can affect the results so it is important to make sure that the test equipment is compliant. In wet areas for high use public buildings, it is important to ensure that a high Slip Resistance Value is obtained in both wet and dry conditions and generally a minimum Slip Resistance Value of SRV 36 should be considered. However, this can be changed in buildings which can clearly establish that areas of their building are dry and uncontaminated. In these situations, it would be possible to use the dry results of the Pendulum Test in order to establish a suitable Slip Resistance. This means that areas such as large circulation areas in airport buildings and shopping centres, which are away from the main entrance areas, can be designated as dry areas and therefore a smoother finish can be provided which will also assist with the cleaning and maintenance of the building. Careful consideration should be given at the design stage to the anticipated and likely prevailing service conditions the finished floor surface will have to endure. There are a number of different factors, listed but not in any particular order, which have to be considered when selecting a flooring product for a particular application Wet or dry Aesthetics and colouration Contamination of the floor finish Coordination with other finishing materials e.g. wall tiles Durability and wearing properties Ease of cleaning and maintenance Method of bedding and compatibility with substrate Product conformance to appropriate standards Ramped floors have more demanding slip resistance requirements Size and scale of flooring units Slip resistance (as supplied and on going through life of installation) The entrance is the most important area, so the introduction of high quality barrier matting for both the initial primary matting and also considering the introduction of secondary matting, external canopies and selection of door types to slow the progress of people entering buildings, will all help to reduce water ingress. The selection of product should aim to satisfy the above and ensure that the flooring material selected is fit for purpose. Slip resistance should be one of the most important design considerations as the safe movement of people over the flooring is Page 8

9 crucial. There are suitable surface textures available to suit a wide range of requirements. For further and more detailed information on Slip Resistance, refer to TTA publication Slip Resistance of Hard Flooring. Traffic conditions See clause 3.7 Thermal conditions Where there are likely to be thermal changes such as in conservatories, atria or where hot water piped underfloor heating or electric cable undertile heating systems have been installed, consultation with the manufacturer with regard to the suitability of the resin agglomerated tile for the envisaged application will be necessary. It is likely that movement joints will be required at a greater frequency than currently indicated within BS and BS i.e. bays of size not greater than 25m² with an edge length not greater than 6m, to accommodate the high thermal expansion of the resin agglomerated tile. Intermittently wet conditions Wet conditions could include showers and wet rooms but not total immersion. Because of the higher coefficients of thermal and moisture expansion, assurances should be sought from the supplier or manufacturer of the resin agglomerated stone tile that it will be fit for the intended purpose and whether any precautionary measures should be taken during and post installation. The frequency of shower use and the ability of the facility to dry out between periods of use would need to be taken into consideration. The shower design should be such that water is quickly and effectively channelled away from the tiled floor area to the drainage outlet in order to keep water contact to a minimum. Consideration may be given to the use of epoxy resin grouts to help provide impervious joints and a proprietary tanking system should be applied to the substrate. Submersed conditions Due to the high degree of moisture expansion the suitability of resin agglomerated tiles in a total immersion situation such as swimming pools, fountains etc. is not recommended. Page 9

10 4.2 Background/substrate Resin agglomerated tiles should be fixed to a dry, flat, cohesively strong, stable and rigid substrate that is free from surface contamination such as dust, laitance, grease, wax, loose or flaking areas etc. In general the moisture content should be determined in line with current standards and the recommendations of substrate manufacturers. Consultation with the agglomerated stone manufacturer should also be undertaken to ascertain the maximum moisture levels permitted prior to the installation of their material. The sub floor may be considered adequately dry when a cement:sand screed registers not more than 75% RH when tested with a flooring hygrometer or not more than 2% using the Carbide method Wall substrate Wall substrates should be strong enough to take the weight of the agglomerated stone and the associated adhesive bed. The guidelines given in BS should be followed. Table 2 Weight restrictions of wall substrates Wall Substrates Unmodified Gypsum Plaster* Gypsum Plasterboard Direct (without a plaster skim) Plywood Lightweight Tilebacker Boards Glass reinforced Cement Sheets Maximum Weight of Tiling per m² 20kg/m² 32kg/m² Up to 30kg/m² Up to 60kg/m². Dependent upon the type and thickness of the board. Consult manufacturer Up to 50kg/m², Dependent upon the type and thickness of the board. Gypsum Fibre boards Approximately 35 40kg/m² *This background is unsuitable for use with resin agglomerated tiles Page 10

11 10mm thick resin agglomerated tiles normally weighs 25Kg/m² 12mm thick resin agglomerated tiles normally weighs 32Kg/m² 20mm thick resin agglomerated tiles normally weighs 50Kg/m² A 1mm thickness of tile adhesive will add a further 1.5Kg/m² Floor substrates Floors that are to be tiled should be free from deflection and should rigidly accommodate the additional dead load. The guidelines in BS and BS should be followed Sand:cement screeds Sand:cement screeds should comply with recommendations of BS and should be sufficiently sound. The surface should conform to surface regularity SR1 Final finishing to SR1 can be achieved by using a smoothing or levelling compound Power floated concrete Power floated concrete should be prepared and finished to category SR1 and be prepared by contained shot blasting or similar Timber boards Timber sub boards should be sufficiently stable and free from deflection. Follow the recommendations laid down in BS5385 3:2007 clauses or and in the Tile Association document Tiling to Timber and Timber based products. Plywood should conform to BS EN which supersedes the current requirements for WPB plywood Raised access flooring The raised access flooring should be rigid with no movement or lipping between adjacent sections. Where possible the floor panels should be screw fixed to the supports, which in turn should be locked into position and firmly fixed to the floor beneath. This is to prevent potential dislodgement / movement at a later date caused by vibration. To further strengthen the substrate it is recommended that the raised access flooring is over boarded. The boarding should be screw fixed at maximum 300 mm centres with boards being laid staggered to avoid cruciform joints. Page 11

12 For best results: 1 layer of minimum 15mm plywood screwed at 300mm centres as defined in BS For more rigidity an additional minimum layer of 10mm plywood or tile backerboard laid at 90 degree angles to each other 1 or 2 layers of moisture stable strong tile backer board, the thickness of which should be ascertained from the manufacturer. Leave a gap around each timber based board of 3 mm in intermediate locations and 6 mm around perimeters and any interruptions in the floor. Fill the 6 mm joints with a suitable elastic sealant. Note: To safeguard against the potential for moisture ingress or condensation within the void beneath the raised access flooring then it is recommended that the backs and edges of plywood sheets used for over boarding are sealed with a suitable moisture impervious sealer. Advice should be sought from the adhesive manufacturer regarding primer selection Tile backer board Seek advice from the proprietary tile backer board manufacturer Uncoupling membranes Anti fracture membranes This type of membrane can prove beneficial where the substrate is less than perfect e.g. for the bridging of stress cracks within the existing floor, or to help in neutralising lateral movement stresses. However, given the higher coefficients of thermal and moisture expansion of agglomerate stone material compared with other tile finishes, anti fracture membranes must only be installed once informed advice has been sought. The use of an anti fracture membrane should not be considered should the installed agglomerated stone tile exhibit a tendency to curl. Waterproofing / tanking The agglomerate stone selected must be suitable for use in wet rooms / showers etc. and used in accordance with the manufacturer s recommendations. As a tiled finish installed using these products is unlikely to provide a watertight barrier the usual precautions in a shower environment will need to be taken. Therefore the substrate will need to be tanked using a suitable waterproof membrane before beginning tile fixing. Further advice can be found in the TTA publication Tiling in wet rooms. Page 12

13 Note that it is inadvisable to install resin agglomerated stone tiles that exhibit or have a tendency to curl due to the effects of moisture in wet rooms or showers Surface membranes Because of the higher coefficient of moisture expansion of resin agglomerated stone tiles it is essential that substrates to which these tiles are to be bonded, are dry. In many cases a concrete or sand:cement screed substrate may be sufficiently cured and consequently free from shrinkage but may still contain high levels of residual moisture. In these cases a surface applied liquid membrane may be used to form a barrier between substrate and stone. When installing such membranes, ensure that the manufacturer s recommendations are followed with regard to maximum moisture content suppression, effective substrate preparation, application techniques etc. Note: Some Surface membranes are designed to combat residual moisture but not rising damp. Therefore ensure that a functioning damp proof membrane has been installed beneath the base slab Tanking systems Seek advice from the proprietary tanking system manufacturer. 4.3 Adhesive and grout selection Before undertaking a resin agglomerated stone tile installation, it is important that particular attention is paid to the choice of adhesive and grout. Due to the high coefficient of moisture expansion any moisture from the adhesive bed can potentially result in warping or curling of the tile. Other physical characteristics such as colour, chemical composition, water absorption, high coefficient of thermal expansion also need to be considered when installing the material Adhesive selection When selecting an adhesive it is important to take the physical properties of the resin agglomerated tile into consideration. As some of these types of resin agglomerated tiles and slabs are susceptible to moisture deformation during the fixing process it is essential to eliminate as much moisture from the adhesive bed as soon as possible after fixing. Clause of BS5385 3:2009 advises To avoid moisture from the adhesive bed distorting resin based agglomerated stone, reaction resin adhesives, or quick drying low alkalinity cement based adhesives should be used. This can be provided by either a rapid drying low alkalinity two part adhesive of cementitious powder and aqueous polymer dispersion, or a rapid drying low alkalinity cementitious adhesive, specifically designed for the installation of moisture sensitive agglomerated stone tiling. In all cases the mixing water should be rapidly hydrated Page 13

14 so that the adhesive bed beneath the tile hardens, and more importantly, dries rapidly. Where the agglomerated stone is especially moisture sensitive then a water free adhesive should be selected such as those based on epoxy or polyurethane resins. When light coloured resin agglomerated tiles are installed there may be advantages in selecting white adhesives, particularly where the tiles are translucent or partially translucent. In general the low water absorption necessitates the use of adhesives that develop high adhesion strength and a strong bond. To accommodate the thermal movement it would be beneficial to select an adhesive with quantifiable deformation performance such as those classified as S1 or S2 to BS EN Thermal expansion of the agglomerated stone can be influenced by any temperature change such as underfloor heating systems, direct sunlight or from general changes in the ambient conditions. BS :2009 clause states To avoid moisture from the adhesive bed distorting resin based agglomerated stone products, reaction resin adhesives or quick drying low alkalinity cement based adhesives should be used. Dependent on which of the criteria above apply, an adhesive conforming to BS EN from the following list should be selected: Reaction resin adhesive, R1 or R2 classification Cementitious two part rapid setting adhesive, C2F S1, C2F S2 Where specifically recommended by the manufacturer select an adhesive which is rapid drying low moisture content rapid setting cementitious onepart adhesive. Note: The use of a cement based adhesive with S2 classification should be used where the loading and traffic conditions are not heavy. Further guidance should be sought from the tile and adhesive manufacturer. The recommendations given are to minimise the water ingress into the back of the resin agglomerated stone tile where there is a potential for warping / curling from the effects of moisture in the adhesive bed. The use of a reaction resin adhesive, or a rapid hardening and quick drying cementitious adhesive will be advantageous. Rapid hardening and quick drying cementitious adhesives with low water content (e.g. two part systems) will also reduce the water ingress into the underside of the tile and reduce the potential for any adverse reaction with the resin binder. Page 14

15 4.3.2 Grout It is important to check with the supplier of the agglomerated stone tiles to establish if the tiles should be sealed before the grouting process begins. If this is the case, to ensure good adhesion of the grout mortar in the joints, care should be taken to ensure that the sealer is confined to the surface of the tiles and that the sizes of the tiles remain untreated. Resin based agglomerated tiles should be grouted with improved cement based grouts classified CG2 to BS EN (e.g. CG2A, CG2W or CG2WA) or alternatively with water free resin based RG grouts. Where cement based grouts are used there may be advantages in using rapid setting and drying cementitious grouts which minimise water contact with the tile. 4.4 Movement joints The type and position of movement joints in resin agglomerated stone tiles should be as described in BS5385 5, however resin agglomerated tiles require movement joints at a higher frequency that take into account the high coefficient of thermal expansion. The type and design of the movement joint should be fit for purpose. In normal conditions movement joints should be installed at bay sizes not exceeding 36m 2 and for underfloor heating not more than 25m 2. The Tile Association document Movement Joints states Like all building materials, resin agglomerated tiles exhibit dimensional changes in response to fluctuations in environmental conditions. BS : 2009 provides advice in clause on the type and positions of movement joints in agglomerated stone flooring should be as described in clause 8, but advises that resin based units require movement joints at a higher frequency that take into account their greatly increased coefficient of thermal expansion. It includes a note that resin based flooring units can have a coefficient of thermal expansion more than three times that of cement terrazzo and natural stone. The sub clauses also include information on the clause dealing with structural movement joints. It also advises that where flooring abuts restraining surfaces such as perimeter walls, columns, kerbs, steps and plant fixed to the base, perimeter joints should be installed unless the distance between restraining surfaces is less than 2 m. Note that movement joints should be placed where the flooring runs across door thresholds and be contiguous with the perimeter movement joints. It is becoming more common to use stone units bedded on to other materials with different movement characteristics. As a result there is a need to provide stress Page 15

16 relieving movement joints to prevent damage resulting from restrained dimensional change which can manifest itself as minor spalling at grouted joints, or fracture and major dislocation of stone units. Where resin agglomerated flooring is subjected to high temperatures (i.e. over heating installations or from strong sunshine) an assessment of the likely temperature range and corresponding linear changes should be made. It is difficult to calculate the anticipated movement with precision but, fortunately, in the majority of cases this is unnecessary. Movement joints are provided in the floor at widths and spacings which are known from experience to be satisfactory and also where movement joints occur in the substrate. The positions of movement joints must be established before work commences. Any movement joints must be properly formed, according to the degree of exposure, with a suitable flexible material. The extension capability and recovery performance of the chosen joint former or sealant will frequently determine the actual joint width. This section suggests spacings and sizes for movement joints in normal environments. It is important that the designed minimum gap is not obstructed. A careful check should be carried out before joints are sealed. Perimeter joints can usually be hidden beneath the skirting Unusual circumstances, novel construction details or contaminated environments will all need special consideration and the extent of any movement should always be carefully calculated. Where day work joints occur in the screed they should be bonded during screed installation as recommended in BS and where movement joints are required in the floor joints should be post cut in the screed during setting out of the floor tiling. Reinforcement in screeds should cross all day work joints to ensure that no unpredicted movement can affect the performance of the agglomerated stone flooring, particularly where the stone is installed using adhesive. Where underfloor heating is used the pipes or cables should be located to ensure that the system is contained within the pattern of movement joints. Movement joints for the flooring described in this code are as follows: a) flexible joints aligned to structural movement joints b) flexible movement joints to accommodate smaller movements than structural joints c) contraction joints which are non compressible to relieve tension Page 16

17 Further information can be found in the TTA publication Movement Joints in Internal Tiling. 4.5 Underfloor heating It is important to consider the high coefficient of thermal expansion of resin agglomerated tiles, see clause 4.4 regarding movement joints. Consult the tile supplier before using resin agglomerated tiles with underfloor heating systems Where large format tiles (i.e. with a single side 600mm or greater) are being used consideration should be given to using wider joint widths. Because there will be a higher rate of thermal movement consideration should be given to using smaller bay sizes. See clause 4.4 The floor should be commissioned as described in the Tile Association document Tiling to heated floors Further information can be found in the Tile Association document Tiling to heated floors Electrical undertile heating systems When using this form of underfloor heating it is important to ensure there is no contact between the heating cable, mesh and the back of the tile. This can be achieved by using self levelling compound or a thin layer of tile adhesive which is allowed to cure and dry before tiles are fixed. 5. INSTALLATION Resin agglomerated tiles should be stored in the areas where they are to be used. Resin agglomerated tiles should not be stored outside and ensure that the temperature when the tiles are being laid is above 5 degree Centigrade in accordance with BS5385 and BS See section 3.5 and 4.3 regarding dryness of the substrate. 5.1 Walls The ideal background for resin agglomerated tiles is sand:cement render or proprietary tile backer board, both of which are dimensionally stable and of sufficient cohesive strength. The background should be checked with a 2 m straight edge to ensure that any gap between points of contact behind the straight edge does not exceed 3mm. Page 17

18 Fixing using a suitable notched trowel and back buttering of the tile should ensure adequate adhesive coverage. Tiles should be checked during the fixing process to ensure solid bedding has been achieved. See Clause 5.3 for grouting process. 5.2 Floors The subfloor should be checked with a 2 m straight edge to ensure that any gap behind the straight edge does not exceed 3mm. Pre smoothing or levelling compound may be used to achieve surface regularity SR1 using a primer where required. Fixing using a solid bed notched trowel and back buttering of the tile should ensure adequate coverage. Tiles should be checked during the fixing process to ensure solid bedding has been achieved. Se Clause 5.3 for grouting process. 5.3 Grouting Grouting should be performed when the adhesive has hardened adequately by referring to manufacturer s instructions. This time period will be dependent on the rate of strength development of the adhesive and site conditions. Cementitious grout should be mixed with the amount of water recommended by the manufacturer. Reaction resin adhesives may require longer curing times. Grouting should not be unduly delayed as open joints might collect general building dust and deleterious substances. Avoid using excessive amounts of water during the grouting process. Cement based grout should be cleaned off within the recommended working time and using the minimum amount of water. Reaction resin grout should be cleaned off within the working time ensuring that all traces are removed from the face of the tile. 5.4 Cutting tiles The preferred cutting method is a rotary wet tile cutting machine. The operator must wear appropriate PPE. Tiles should be wiped dry after cutting. Tiles can also be cut using a dry angle grinder. Page 18

19 Care should be taken to immediately remove any residue from the tile before fixing, especially from the back and side. It is not possible to cut these tiles using a standard scribe and snap cutter. Resin agglomerated tiles should be drilled with a drill with a water feed and dried immediately afterwards. 6. TOLERANCES Local variations in level for a nominally flat floor should be such that, when checked with a 2 m straightedge, any gap under the straightedge, between points of contact, does not exceed 3 mm. There should be no appreciable difference in levels across joints and the maximum deviation between tile surfaces on either side of the joint should be: For joints less than 6 mm wide, 1mm For joints 6 mm or wider, 2 mm 7. HEALTH AND SAFETY 7.1 Handling Correct handling should be observed ensuring that all operatives have received training in the correct lifting techniques. Some large pieces of resin agglomerated tile could weigh in the region of 36kg per piece, which exceeds the requirements for manual handling for a single person to carry, it is therefore imperative that the slab is lifted by 2 or more people or alternatively using suitable mechanical handling equipment. 7.2 Cutting/dust Operatives must be competent in the use of all cutting and drilling equipment and test certification must be available for all mechanical/electrical equipment used on site. Wherever possible the use of a wet cutting machine is recommended in order to ensure a good quality edge is achieved and also to reduce the amount of dust during the operation. The operative must wear protective ear defenders and goggles and always clean and dry the pieces after they have been cut. If dry cutting blades are adopted the operative must be equipped with ear defenders, mask and goggles in accordance with the site safety procedures and wherever possible with extract facilities to reduce the dust levels. Page 19

20 Equipment must be regularly checked and maintained to ensure that noise levels are kept to a minimum. 7.3 Chemicals/adhesives Safety data sheets should be provided for all products used in the installation of Resin Agglomerated tiles. Any exposure advice should be followed. 7.4 Risk assessment and method statements (RAMS) All operatives are required to read and understand RAMS as prepared for each project prior to starting work on site. 7.5 Slip resistance Slip resistance of floors is normally measured by BS 7976 Pendulum Test which measures the co efficient of friction in both wet and dry conditions. Most architects and designers will require test results on the materials specified for a project in order to ascertain the performance of the tile finish. However in accordance with HSE requirements it is imperative that the areas are defined as wet or dry environments so that a decision can be made on the most suitable finish. The slip resistance of floor finishes is drastically affected by the introduction of impregnator sealers and polishes which could reduce the slip resistance performance Correct cleaning and maintenance procedures are essential. 8. ENVIRONMENT Resin agglomerated tiles are manufactured using a high proportion of recycled natural stone waste taken from granite and marble quarries after the normal stone cutting process. Some quartz tiles include recycled glass. Some special resin (binder) is produced from collected and recycled plastic (PET) bottles. All waste materials and rubbish must be cleared as work proceeds and segregated in accordance with site requirements into appropriate skips as provided on site. 9. CLEANING AND MAINTENANCE Steam mops should not be used for cleaning resin agglomerated tiles. On installation of these tiles, it is important to ascertain whether these tiles will require sealing. Ideally this information should be known by the supplier and advice given. Page 20

21 Marble based resin agglomerated tile may require sealing depending on the manufacturer s recommendations. Always ensure that the correct impregnator is used; most water based sealers will be repelled by the resin binder in the tile. The use of a solvent based product will be required in most cases, always test on an un laid tile before treating the whole area as some solvent products may cause damage to the surface structure of the tile. Pre sealing some resin tiles will also greatly facilitate the removal of the grout residue. It will also protect against possible bleed, tram lining or picture framing. These expressions describe the shadowing that an unsealed tile can show if the face and edges are not sealed. This effect can be caused by moisture, sometimes contaminated with grout colourant, which can be absorbed into the edges of some resin tiles. Such staining can be very difficult to remove from these tiles. Seek advice from the manufacturer or supplier. Please Note; some impregnator or sealer manufacturers may recommend a minimum time before the grouting process is commenced in order to leave sufficient curing time for impregnators/sealers. Always follow manufacturer s guidelines. Installation/builders clean After the grouting is completely dry, the floor may need a gentle wash to remove any residue of grouting, or any grease or grime marks that may have occurred during the installation processes. A mild alkaline product formulated specifically for this process can be used in conjunction with a white non scratch pad. Always follow the manufacturer s instructions. It is recommended to clean a test area. If the problem persists contact the manufacturer or supplier for appropriate product and application advice. Daily/weekly maintenance Using the correct maintenance products on resin agglomerated tiles is not only the key for the longevity of the impregnators (if used) but also ensures the surface of the tile remains in good condition. Damage can occur to a tiled finish by misuse or incorrect maintenance due to inadequate instructions. Clients or personnel, responsible for the maintenance of such floors, should ideally be given full information by the supplier; this includes a full cleaning and maintenance schedule. Ideally all floors will be vacuumed (brushes down) or brushed to remove any surface grit and dust. The floor will then be washed over using a proprietary cleaner, which is ideally applied with a sponge mop (larger areas can be completed with driven Page 21

22 cleaning machines). This should ensure that any excess water and dirt is carried away and not left on the surface or in grout joints to evaporate. Some daily cleaners may need rinsing other will require natural drying, always follow the manufactures instructions for best results. Deeper cleaning All floors will require a general maintenance schedule, which will indicate when a deeper clean is required i.e. spring clean or a general refreshing of the surface finish. Any stubborn stains (e.g. rubber shoe marks, light oil stains or dirty grout) can normally be removed with specific multi purpose cleaner. Care should be taken with these deeper cleaners, as excessive use can have an effect on resins. Always follow manufacturer s instructions or contact them for detailed instructions of use. Household and commercial cleaning products must be used with caution as they may contain bleaching agents, or ingredients that may burn or discolour resin finishes. Contact the manufacturer or supplier for advice and product information. 10 REFERENCES AND BIBLIOGRAPHY BS EN 636 3:2003 Plywood. Specifications BS :2009 Wall and floor tiling. Design and installation of ceramic, natural stone and mosaic wall tiling in normal internal conditions. Code of practice BS :2006 Wall and floor tiling. Design and installation of external ceramic and mosaic wall tiling in normal conditions. Code of practice BS :2007 Wall and floor tiling. Design and installation of internal and external ceramic and mosaic floor tiling in normal conditions. Code of practice BS :2009 Wall and floor tiling. Design and installation of ceramic and mosaic tiling in special conditions. Code of practice BS :2009 Wall and floor tiling. Design and installation of terrazzo, natural stone and agglomerated stone tile and slab flooring. Code of practice BS :2003+A1:2009Part 1: Concrete bases and cementitious levelling screeds to receive floorings Code of practice BS EN 12004:2007 Adhesives for tiles definitions and specifications BS EN 13888:2009 Grouts for tiles Definitions and specifications BS EN 14617:2008 Agglomerated Stone Test Methods BS EN :2005 Agglomerated stone. Test methods. Determination of apparent density and water absorption BS EN :2008 Agglomerated stone. Test methods. Determination of flexural strength (bending) BS EN :2005 Agglomerated stone. Test methods. Determination of abrasion resistance BS EN :2005 Agglomerated stone. Test methods Determination of freeze and thaw resistance. BS EN :2005 Agglomerated stone. Test methods. Determination of thermal shock resistance. Page 22

23 BS EN :2005 Agglomerated stone. Test methods. Determination of impact resistance. BS EN :2005 Agglomerated stone. Test methods. Determination of chemical resistance BS EN :2005 Agglomerated stone. Test methods. Determination of linear thermal expansion coefficient. BS EN :2005 Agglomerated stone. Test methods. Determination of dimensional stability BS EN :2005 Agglomerated stone. Test methods. Determination of electrical resistivity. BS EN :2005 Agglomerated stone. Test methods. Determination of compressive strength BS EN :2005 Agglomerated stone. Test methods. Determination of dimensions, geometric characteristics and surface quality of modular tiles. BS EN 14618:2009 Agglomerated Stone BS EN 15285:2008 Agglomerated stone. Modular tiles for flooring and stairs (internal and external) British, European and International Standards are available for purchase from the British Standards Institution, 389 Chiswick High Road, London W4 4AL The Tile Association documents: Movement Joints in Internal Tiling The Cleaning of Ceramic Tiles The Slip Resistance of Hard Flooring Tiling to Timber and Timber based products Tiling in Wet Areas Tiling to Heated Floors 11. MEMBERS OF THE WORKING GROUP Billy Valler Bob Howard Bob Sewell Brian Newell Colin Stanyard Cyril Potter David Wilson Don Slade Lesley Day Lisa Breakspear Lorna Williams Neil Sparrow Peter Dawson Richard Friebe Shelley Johnson Page 23