How to lay parquet flooring?

The process of installing parquet is quite a difficult and responsible task. Its quality depends not only on the skill of the installer and the availability of all necessary tools and materials, but also on the installation method. Parquet is mainly installed using the following methods:

Method 1: Directly onto concrete

Method 2: Onto a plywood layer

Method 3: By installing plywood over joists

In this article, we will explain the most commonly used method of installing parquet by laying plywood over joists.

Before laying parquet, it is essential to check the dryness of the subfloor. If screed has been laid to smooth the subfloor, its moisture content must be measured after it has dried. The moisture content of the concrete subfloor should not exceed 3%. At the same time, the dryness of the plaster applied to the walls should not be overlooked. Because dry wood materials (with a dryness level of not less than 10-12%) are hygroscopic, they can absorb moisture when used in a humid environment and lead to problems later on.

Work can begin once you are completely sure of the subfloor's dryness. First, the area where the parquet will be laid is measured, and the number of plywood sheets required for this area is determined. The thickness of the plywood to be laid on the floor should not be less than 12 mm. For this thickness of plywood, the distance between the joists (lagas) should be 25.4 cm, and 9.2 meters of joist (laga) are calculated for each sheet of plywood. If 15 mm plywood is used, it is possible to reduce the number of joists by 1.

After the subfloor is cleaned, the joists are laid out, and the floor level is determined. Wooden shims (opposite pairs) are used when measuring the level. The wooden shims are adhered to the concrete surface with PVA-based or polyurethane-based PUR adhesive. ("FAB SUPER UNIVERSAL ADHESIVE", "FAB PUR - 601", "FAB PUR 676" adhesives can be used). The leveled joists are fastened to the subfloor with screws. Depending on the unevenness of the subfloor, the screws can be 80, 100, 120 mm long and 6 mm in diameter. It is not essential for the screws to be fully threaded; half-threaded screws are more suitable.

After the joists are installed, the spaces between them are cleaned of sawdust and debris. The selected plywood sheets are then attached to the joists. It is recommended to apply Mobitex wood protector to the plywood and joists before installation. This protects the plywood from mold, fungi, and woodworms. ("FAB MOBITEX WOOD PROTECTOR" can be used). When installing the plywood, it should be fastened 8-10 mm away from the walls.

To prevent sliding, wooden or plastic shims are placed in the gaps. For fastening, it is recommended to use 5x50mm and 5x60mm screws. To avoid gaps between the plywood and the joists, we drill holes with a 5.5 mm drill bit. As a result, the screws pass through the plywood smoothly, and no gaps remain. Gaps can create unpleasant noises in the flooring.

Do not do these things when laying parquet

Some people cover the plywood after installation to prevent it from getting dirty, or they leave this task for last. This is incorrect. Phenol-formaldehyde resin-based acids are used in the production of plywood, which later rise to the surface due to heat. As a result, this negatively affects the adhesion of the parquet to the plywood. Since soiled plywood needs to be sanded, the sanded surface's adhesion potential increases. The adhesive's grip improves.

Our subfloor is now ready for parquet installation. We can begin work after the parquet selection and laying pattern are determined. It is advisable to lay the parquet towards the light.

Parquet can be divided into two groups: lacquered and unlacquered. Lacquered parquet is usually laid after the renovation is fully complete. Sometimes the underside of such parquet is also lacquered. In this case, one- or two-component organic-based adhesives are used. With such adhesives, parquet can also be glued directly to concrete. Unlacquered parquet is laid with PVA-based adhesives. ("FAB UNIVERSAL ADHESIVE", "FAB PVA PARQUET AND WOOD ADHESIVE" products can be used.)