Note that the sub-flooring must be level! When installing a WiseLoc locking system, the greatest subfloor height difference allowed is ±1mm per 1 metre.
The levelness of the sub-floor can be checked by placing a floorboard tongue against the sub-floor and measuring the gap remaining between the sub-floor and the floorboard. Excessive height differences must be levelled out by grinding or applying appropriate filler material. The sub-floor must be immovable, strong, solid, straight, dry and clean. All fitted carpeting must be removed. Suitable sub-floors include: wooden or chipboard flooring, concrete surfaces, flagged and marble floors, linoleum or PVC. Note that concrete surfaces always require a moisture barrier! (E.g. 0.2mm thick construction plastic, seams overlapped approx. 200mm or taped.)
Other construction work
All other construction work must already be completed. If other construction or surface work is carried out in the room after the flooring has be installed, the floor must first be tidied with a vacuum cleaner, after which it must be protected with a moisture-permeable material (e.g. cardboard). Remember to ensure that the material does not discolour the flooring. When the flooring has been covered, the underfloor heating MUST NOT BE SWITCHED ON!
Storing of packages and quality inspection
The packages must be stored unopened and loosely stacked in the room which must be dry, with a relative humidity [RH] of 40-60% and a temperature of +18-24 C°. The packages must remain in a room temperature equal to the installation room temperature for 2-3 days before the installation. Open the packages only when you are about to begin the installation, and only use a few packages at a time (to obtain a floor as evenly coloured as possible, alternate the floorboards from different packages while installing the flooring). Before installation, check the floorboards under proper lighting. If product defects appear, do not install the floorboard! The manufacturer is exempt from liability in complaints where floorboards have been installed on the sub-floor without quality inspection.
Room air’s relative humidity and temperature
To ensure long-term durability of the flooring, it is particularly important to monitor the relative humidity (% RH) of the room; during and after installation, the RH should remain between 40% and 60%. Wood is hygroscopic, and reacts to changes in relative humidity either by absorbing or losing moisture (when RH > 60%, wooden materials, including flooring, will expand; when RH < 40%, wooden materials shrink). If the relative humidity of the room is not properly addressed, gaps or fissures may develop in the flooring. The relative humidity of a room can be adjusted, for example, by using an air humidifier during winters and by ventilating the room during summers.
The room temperature must be between +18C° and +24C°.
Underlay materials and tools
Ensure that the sub-floor is dry and level and that the underlay materials (moisture barrier and sound insulation material, when required) as well as tools required for the installation are available.
Impact sound insulation materials include: Foamed plastic, Timberstep textile underlay material (requires a separate moisture barrier) or Tuplex (contains a moisture barrier).
Required tools include: Metric measuring tape/ruler, marker pen, try square, fitting wedges for expansion joints, circular or crosscut saw, clamping device, wooden knocking block (for knocking floorboards into place), chisel + hammer, knife, wood glue (PVAC glue).
Humidity of the sub-floor before installation
The relative humidity of the sub-floor should be measured before installation. Ensure that the sub-floor is dry throughout the whole installation area (also under any stored construction materials). Sub-floor humidity is easy to assess by spreading an approx. 1m²-plastic sheet over the sub-floor for 24 hours, sealing it tightly by taping the edges. Any humidity that accumulates underneath the plastic sheet and on the surface of the sub-floor (concrete) indicates excess evaporating humidity: this means that the installation should not yet be started. Precise sub-floor humidity measurements can be obtained by using the appropriate moisture meters. f the relative humidity of the sub-floor is higher than 80% (max weight percentage 3.0), DO NOT start installing the flooring!
Preparation for the installation and expansion gaps
First calculate the number of floorboards you require. Use a metric measuring tape/ruler to measure the total width of the room; divide it by the width of a floorboard, and check how many complete rows of floorboards will be used for the room. Also narrow off the first row of floorboards if the calculations show that the width of the last row of floorboards will be less than 50mm. If the width of the room is considerably less than its length, it is recommended that the flooring is installed in parallel with the room’s maximal length. In other cases, we recommend that the floor is laid in the line of light. When installing flooring equipped with the WiseLoc locking system, it is easiest to start near the wall which contains most of the doors in the room. If one of the room’s gable walls contains door(s), start the installation near that wall. Start from the corner and install the floorboards sequentially, moving from left to right.
To account for the expansion/shrinkage of the flooring with respect to fluctuations in air humidity, an approx. 10mm gap must be left between the walls and the flooring during the installation. Such a gap is also left around heating ducts, doorframes, pillars, etc. Expansion gaps left in front of doorways or floor raisings (e.g. stairs, thresholds, etc.) should be covered with appropriate skirting boards. In large continuous rooms (over 10m long or over 8m wide), it is necessary to prepare for larger expansion gaps. Make use of thresholds, for example. The main rule is that an expansion gap of 10mm is sufficient for a room that is 6m wide, and that for every additional metre, the expansion gap must be increased by 1.5mm.