Before bonding the flooring, it is essential to check that the under-surface is in good condition. Check, above all, its moisture content and cohesion and if these parameters are correct, move directly to bonding.
If the under-surface is in poor condition, proceed as follows:
- If the residual moisture content is too high, wait for the under-surface to dry out at least until the moisture content is within the limits for using a water-proofing primer. If the under-surface is heated, self-levelling or made of anhydrite, water-proofing may not be used.
- If the under-surface shows a serious lack of consistency it should be consolidated, but if it is only slightly crumbly, a suitable primer may be used. Solvent-based primers must not be used on flooring with heating.
In order for the primer to be properly applied, the under-surface must be free from dust or other processing residues. It should therefore be cleaned with a vacuum cleaner or other cleaning system before proceeding any further.
Once the under-surface is clean, a coat of water-proofing or consolidating primer, as required, may be laid. The primer can also be applied with a paintbrush but it is more usually applied with a long-haired roller. If a waterproofing primer is being used, a second coat should be applied once the drying time between coats has elapsed. Great care should be taken to avoid localised build-ups of the primer that would make the surface too smooth for effective bonding.
Once the preparatory operations have been completed, the under-surface should be checked again to ensure it is clean and free from dust and other processing residues before applying the adhesive.
Depending on the type of adhesive chosen, it should be prepared as required, in the case of bi-component adhesives by mixing these together. The pot life should also be checked to avoid preparing more product than will be used within the prescribed time. Whatever adhesive is to be used, it is good practice to spread the adhesive on floor areas that are small enough for the flooring to be laid before the hardening process begins.
If wood flooring is to be bonded, the adhesive can be spread with a wide-groove spatula (10 mm), but if other materials are being bonded, such as cork, linoleum, carpet, rubber, etc., we recommend using a narrow-groove spatula, 5mm or even smaller, if the material is particularly thin.
To calculate the amount of glue needed it is essential to check the under-surface roughness and porosity because these factors, if high, can necessitate using considerably more product.
For bonding traditional parquet which is not mosaic and has no joints, the adhesive should also be spread on the short edges of the parquet strips to give the whole system greater stability.
After bonding, any further processing and, for pre-varnished flooring the introduction of furniture, must only be carried out once the adhesive is completely dry, a period of time that varies from system to system, but in all situations is no fewer than 72 hours from when the flooring was laid.