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					Ruabon Quarry Tile Technical Data Sheet No. 7                                                                                       Member of

Issue No. 4 March 2007                                                                                                               The Tile

Fixing Methods 1
Specific Requirements                          Cement based adhesives are generally            With standard adhesives, tiles can gener-
                                               mixed with clean water to form a smooth         ally be adjusted in position for up to 20
It is critical, when fixing quarry tiles by    paste, free from lumps, and are applied         minutes and the floor will be ready for
any method, that the following recom-          directly to the floor with an 8mm or            grouting after 24-36 hours depending on
mendations are observed:                       10mm notched trowel. The bed should be          type of substrate and ambient tempera-
• Ensure that reputable tile fixers are        combed at a slight angle to produce a           ture. During this period it it is essential to
engaged for the project, preferably regis-     ribbed finish.                                  protect the tiles and their bedding from
tered with The Tile Association.                                                               foot traffic, the elements and any other
                                                                                               potential disturbance.
• Ruabon quarry tiles should be fixed in
accordance with BS 5385, which is the                                                          Rapid-set adhesives
code of practice for installation of ceramic                                                   These are used and applied as standard
floor tiles                                                                                    adhesives except they have reduced open
• Planning and preparation of surface to                                                       times. They enable a floor to be quickly
be tiled should be in accordance with                                                          brought into service enabling grouting to
Ruabon technical data sheets 1 and 2.                                                          be carried out as quickly as 3 hours after
• The contents of several boxes should be
thoroughly mixed before fixing to achieve                                                      Flexible adhesives
the maximum benefit from the natural           Tiles should be pressed firmly into posi-
                                                                                               These are used for more demanding appli-
shade variations inherent in the product.      tion with a slight twisting action. It is
                                                                                               cations requiring improved adhesion,
• The tiles should be fixed with the under-    essential to ensure each quarry tile is fixed
                                                                                               waterproofing and/or elasticity to counter
side fixing ribs all facing the same direc-    on a solid bed and that the entire tile back
                                                                                               the effects of minor movements and de-
tion to minimise the effect of allowable       is in full contact with the adhesive. Tiles
                                                                                               flections. They are commonly supplied
size differences which may exist and are       should be lifted periodically as work pro-
                                                                                               with a built in admix and are simply
characteristic of a natural clay product.      gresses to check this. Any voids under-
                                                                                               mixed with water prior to use. Typical
                                               neath tiles will be a potential point of
If contact with, or containment of, aggres-                                                    applications are under-floor and under-tile
                                               weakness under load and in exterior situa-
sive chemicals is envisaged, then a suitably                                                   heating, fixing to existing tiling, smooth
                                               tions water may accumulate giving rise to
resistant fixing method and chemically                                                         asphalt and fixing to suitably braced tim-
                                               frost damage.
resistant grout will be required.                                                              ber substrates. It is essential that a com-
                                                                                               patible flexible grout is used. Further
Fixing using           c em e n t - b a s ed             Ensuring tiles are solidly bedded
                                                                                               details on such installations can be found
adhesives:                                                                                     in Technical Data Sheets 5, 9 and 12.
There are alternative methods of fixing                                                        Pourable adhesives
such as traditional sand/cement mortar
and semi-dry bed methods but these are                                                         To achieve a solid bed usually requires the
generally inferior to modern day tech-                                                         tiles to be buttered prior to placing onto
niques and should only be undertaken by                                                        the ribbed bed so no voids are left beneath
experienced fixers.                                                                            tiles. Pourable adhesives such as Ardex
The most popular and generally recom-                                                          S21 are specially formulated to ensure
mended method of fixing floor tiles is by                                                      solid bedding without the need to butter
                                               Tile spacers should not be used on natural
use of a good quality cement-based adhe-                                                       the backs of tiles.
                                               quarry tiles and grout lines should be
sive such as Ardex products.                   maintained to give a minimum joint              Epoxy adhesives
These can be used to produce a finished        width of 6mm for subsequent grouting.
bed thickness from 3mm up to 15mm                                                              A 2 part resin/hardener system for full
depending on product type. The base            Any surplus adhesive should be cleaned          chemical resistant bedding and for fixing
surface to be tiled requires close surface     from tile faces before it begins to set.        to metal surfaces.
tolerances as irregularities are more diffi-   Manufacturers instructions should be fol-
cult to accommodate in the relatively          lowed with regards to open times of adhe-
small depth of bedding. Use of a suitable      sives. Once this time has expired any ad-
proprietary self-levelling compound is         hesive should be discarded and a fresh
generally the best method of attaining a       batch mixed.
flat and level base for tiling.
Dennis Ruabon Sales, Hafod Tileries, Ruabon. Wrexham LL14 6ET. Tel:
01978 843484 Fax: 01978 843276 E-Mail:  
Ruabon Quarry Tile Technical Data Sheet No. 7                                                                                                Member of

Issue No. 4 March 2007                                                                                                                        The Tile

Fixing Methods 2
Fixing using sand/cement mortar                  Semi-dry using separating layer                        Application of tiles
                                                 (unbonded method)
                                                                                                         The tiles should be placed on the slurried
   This is now a somewhat dated method
                                                  A separating layer should be used over                bed with care taken to avoid depressing
of fixing quarry tiles and requires a high
                                                 suspended floors subject to significant                one of the corners. Tiles should be tapped
level of skill to obtain a good quality in-
                                                 deflection, e.g. made from thin-section                firmly into position using a rubber mallet.
stallation. There are three main methods
                                                 beams, planks or slabs or if the condition             It is beneficial to butter the backs of tiles
of fixing:-
                                                 of the subfloor prevents adhesion for any              with a mortar of 1:2 cement/sand.
Bedding directly in mortar                       reason.
                                                                                                        Alternatively traditional “beating in” can
 Only suitable where the base is com-            In this method a separating layer or mem-              be carried our using a flat faced wooden
pletely mature, no risk of shrinkage exists      brane is interposed between the bed and                block, which, dimensionally, is usually
and a damp-proof membrane has been               the base. A layer of polyethylene sheet,               approximately 300 x 100 x 50mm. Some
incorporated during construction. It is not      bituminous felt or building paper should               flooring contractors use vibrating ma-
suitable for floors containing under-floor       be laid over it and the joints taped and               chines for beating-in. During this opera-
heating.                                         lapped at least 100mm. A semi-dry mix as               tion the tile joints should be regulated (6-
                                                 described previously is laid over this at a            10mm) and an occasional check made to
The substrate must be clean, sound and
                                                 minimum of 40mm and reinforced with                    establish that full contact is being achieved
reasonably smooth. The bedding mix
                                                 steel fabric incorporated within the mid-              between tiles and the slurried bed by lift-
should be 1:3 to 1:4 cement/sand laid
                                                 dle third of the bed thickness,                        ing a tile out at random; any slurry or
between wooden fillets 15—20mm thick.
                                                 lapped100mm and wire tied.                             mortar disturbed should be made good
The mortar bed should be levelled by
                                                                                                        before the tile is replaced.
tamping across the supporting fillets            A consistent bed thickness is important
which must be removed as work pro-               with unbonded floors.                                  It is important that there is no delay be-
gresses. It is essential that there is no free                                                          tween spreading the slurry and fixing the
surface water on the bed as this will in-                                                               tiles.
hibit adhesion. The quarry tiles should be
firmly tapped into the mortar to produce         Thickness of tile bedding—as specified in BS 5385 Part 3
the required level. The adhesion of the
                                                 Bedding method            Sub-floor surface   Bed thickness           Comments
tiles may be improved by the application                                   regularity
of a cement slurry immediately prior to
                                                 Adhesive bed (see 7.2.1) SR 1                 1mm to 6mm              Adhesive bed thickness
fixing.                                                                                                                should be within the range
                                                                                                                       recommended by manufac-
Bedding in semi-dry sand/cement                                                                                        turer
mortar (bonded method)
                                                 Bonded Cement:sand        SR 2                15mm to 20mm            For tiles thinner than 10mm a
 The substrate must be clean, sound and          mortar bed (see 7.2.2)                        (tile thickness         bed thickness of 10mm to
                                                                                               greater than 10mm)      15mm is recommended
reasonably smooth. The bedding mix
should be 1:3.5 to which water is added at       Unbonded semi-dry         SR 3                40mm to 70mm            Steel fabric reinforcement
the ratio of 0.55 to 0.6 by weight (about        cement:sand mortar                                                    might be required in the bed,
                                                 bed                                                                   e.g. on suspended floors. (see
27.5 litres water:50kg cement). The mix          (see                                               
should be spread to a thickness of 10% to
                                                 Bonded semi-dry           SR 3                40mm to 70mm            Maximum thickness 100mm
15% greater than that required for the           cement:sand mortar                                                    where falls are formed within
actual bed and thoroughly tamped and             bed (see                                                     the bed
drawn off to the required level.                 The bedding of tiles in a semi-dry mix permits the laying to be carried out to a much greater thick-
                                                 ness in a single operation than can be achieved using a standard sand and cement mortar.
No greater area of mix should be spread
than can be tamped and topped with               It also allows for floors to be either bonded or laid over an isolation membrane.
slurry and tiles in one continuous opera-        Where a floor is not to be isolated the preparation given in is particularly important as the
tion. A cement slurry should be immedi-          dryness of the mix described in results in weak adhesion between the bed and the base.
                                                 Cleavage can occur at the interface in the event of differential movement, to the detriment of the
ately spread and trowelled over the bed in       floor.
an even layer about 2mm thick to which
                                                 Where a uniformly thick bed can be applied to achieve the required level of the tile surface, 70mm
the tiles are placed and tapped firmly into      maximum thickness is usually the most practical. Where falls have to be formed entirely in the
the bed to the required level.                   bed, its greatest thickness is 100mm. In all cases, the minimum thickness should be 40mm.

Dennis Ruabon Sales, Hafod Tileries, Ruabon. Wrexham LL14 6ET. Tel:
01978 843484 Fax: 01978 843276 E-Mail:  

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