Floor preparation for self adhesive flooring tiles
Self-adhesive flooring vinyl tiles can be easily laid by the average householder to give a professional and attractive finish to the floor. While these tiles can be laid in any area of a home, they are generally restricted to kitchens, bathrooms, utility rooms and other areas where a wipe clean floor surface is desired.
As with most DIY jobs, the final appearance of vinyl tile floor covering largely depends upon preparation, in this case of sub-floor on which the tiles are to be laid. .
Start by stripping off any old, damaged or uneven floor coverings; make sure that the surface is firm, clean, flat and smooth. If you intend laying over existing tiles, ensure that these are firmly stuck down - if in doubt, remove them.
The sub-floor must be completely free of paint, oil, grease, bituminous compounds and any solvent based materials.
Concrete floors must incorporate a damp-proof membrane. Newly laid concrete floors must be allowed to dry out completely - the recommended time, with adequate ventilation, is 1 day per mm (1 inch per month) up to 50 mm thickness. More time will be needed for greater thicknesses. Cold, wet weather will slow down the drying process and require more time.
After the floor has dried out, use a suitable self-levelling compound to repair depressions and uneven concrete surfaces (see how-to).
If a floor of sand and cement screed is considered level enough, seal it with a suitable primer - otherwise use a suitable self-levelling compound (see how-to).
Think carefully before laying tiles on timber floorboards; electric and plumbing services often run under floorboards and it will be next to impossible to remove and reuse the tiles and sub-floor if they have to be lifted. A more satisfactory flooring may be roll vinyl material which normally only needs to be stuck down along some edges.
Remove protruding nails by hammering them below the surface and secure any loose boards. Do not lay vinyl tiles directly onto new boards as the boards may shrink. Sub surface irregularities show through so level warped or worn boards by filling, sanding, planing or, preferably by covering with 6 mm exterior grade plywood or hardboard (smooth side up). Secure the sheets at 150 mm (6 inch) centres all over the sheets using screws or nails - use annular ring nails to reduce the possibility of the nails working up into the tiles. When using hardboard, the sheets should be dampened 24 hours before installation so that they can be laid flat and this should prevent subsequent unevenness.
Always ensure that floorboards on ground floors are adequately ventilated beneath.
Use of a suitable floor primer on all absorbent timber surfaces such as plywood, hardboard and chipboard.
Timber treated with wood preservative is not suitable as a sub-floor, even if overlaid - the fumes from the preservative can affect the tile adhesive.
Ensure that the final surface is completely dry, smooth and firm with no sign of paint, grease, wax, polish, etc. Brush clean to give a completely dust-free surface.
Provided the tiles are sound and are protected by an underlying damp-proof membrane, skim over the tiles and fill the joints with a latex screeding compound in preparation for laying the vinyl tiles.