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Technical guide
Hardness
Use cement based products for subfloor preparation. They must be neither crumbly nor flaky.
Flatness
Maximum deflexion, for a 2 m ruler 7 mm, for a 0.20 m ruler 2 mm.
Surface state: fine and regular.
Dryness
Moisture content in subfloors should be measured using appropriate devices and should be in accordance with relevant
standards in each country. The relative humidity must not be higher than 75 % R.H.
Adapt the drying time according to how cold or damp the conditions are.
Smoothness
A smoothing compound must be applied to the entire surface according to the standards mentioned above. Smoothing
compounds are not designed to overcome levelling deficiencies. The smoothing compound must be allowed to dry in
accordance with manufacturer's instructions.
Rub down using a carborundum stone in order to obtain a perfectly smooth surface.
Sweep or vacuum up any dust. Spread the adhesive.
Expansion joints or movement joints
Floorcovering should be laid up to the joint and the joint should be covered with an appropriate plastic or metal sliding
joint cover.
Subfloors direct to ground
A damp-proof membrane must be laid under the concrete to act as a waterproof barrier against underlying hydrostatic
pressure and moisture.
Underfloor heating
The subfloor must be allowed to dry in accordance with local standards.
The heating system should have been switched on at least 4 weeks before laying the floorcovering, then switched off 24
hours before any subfloor preparation, and remains switched off during installation of the floorcovering.
The heating should then be switched on 48 hours after installation of the flooring and the temperature progressively
increased to normal working temperatures over 5-7 days.
Glueline temperature < 28 °C (contact technical department for further information.)
Old carpeting
Remove, clean the subfloor and apply a smoothing compound.
Wooden floorboards
Check the condition of the floorboards, secure any loose boards.
Any knotholes to be filled as necessary.
Cover with hardboard, chipboard or plywood, minimum thickness 8 mm.
These sheets should be nailed or stapled every 10-15 cms.
Check that the floorboards are dry and ventilated on the underside.
All non ventilated woodenfloors must be removed.
Ceramic tiles
Any loose tiles must be stuck down and any traces of paint, plaster, grease, etc, must be removed. The cleaned tiles must
be primed with an appropriate primer prior to applying a smoothing compound fully in accordance with manufacturers
instructions.
Leave to dry then rub down to a smooth finish.
Sweep thoroughly. Apply the adhesive in accordance with manufacturers instructions.
Old vinyl flooring
Old vinyl, linoleum and rubber floorcoverings should always be removed and the subfloor be examined and prepared as
necessary before installing new floorcoverings.
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Technical guide
Laying procedure for tiles
Unpack the tiles 24 hours before laying and make sure they are stacked horizontally.
Minimum ambiant temperature must be 15 °C.
1. Trace a line perpendicular to the main entrance.
Trace a perpendicular line to this axis ensuring equal cuts for tiles on both
sides.
2. Apply adhesive to a few square metres of subfloor in one quarter.
Insufficient open time of the adhesive will cause bubbles.
If open time is too long the adhesive transfer will be poor.
3. Press each tile into position ensuring joints are butted tight.
Beware installation directions according to pattern.
4. Smooth down manually then roll with a 50 kg flooring roller.
5. If necessary heat weld seams 24 hours after installation.
Do not traffic the floorcovering for 48 hours after installation.
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