Installation with underfloor heating

A good under-floor heating system, either electric or hot water based, is a great heating method for wooden floors as well, giving plenty of comfort for living and a pleasantly warm floor underfoot. Timberwise wooden floors are highly suitable to be used together with underfloor heating and, by taking the following issues into account, you will ensure that your floor works well with underfloor heating. Although Larch is not recommended to be installed with underfloor heating if you are not able to guarantee a permanent condition of relative humidity between 40 – 60Rh. In drier conditions cracks may appear. When considering this, also Larch can be installed with floor heating system.

Important issues when installing on top of underfloor heating include the following:

  • The floor’s surface temperature must not rise above +25°C. This includes surfaces covered by loose carpets and furniture. Note that regular loose carpets raise the floor’s surface temperature by about +2°C!
  • Floor temperature must not fluctuate regularly by more than 2°C; hence, night-time electric heating is not recommended for Timberwise flooring.
  • Under-floor heating must be installed under the entire floor, not just under walk paths, since underfloor heating must distribute heat evenly over the whole floor surface.
  • Under-floor heating dries the air in the room as well as the parquet! Thus, it is important to maintain relative humidity of room air and ensure that it remains between 40% and 60% in any season. The relative humidity in the air can be increased using an air humidifier and through normal living: cooking, using the sauna, growing plants. If the relative humidity of room air decreases below the recommended limit, gaps might appear in the floor.
  • A moisture barrier (0.2mm-thick construction plastic, seams overlapped approx. 200mm or taped) must ALWAYS be installed together with underfloor heating facilities, regardless of the sub-floor material (even wooden floors require a moisture barrier when underfloor heating has been installed).
  • Use an expansion gap to separate floor areas which do not have underfloor heating.
  • Under-floor heating cables or ducts must be installed at no less than 30 mm distance from the underlay material of the Timberwise product.
    • in wooden flooring an air space
    • in concrete floors a filling layer

Installation on top of under-floor heating

  • Prior to installation, the sub-floor must be dried for about 2 weeks.
  • Raise the under-floor heating temperature daily by about 5°C until at least half of the full heating capacity is utilised. After this, use the maximum heating temperature for three days; the heating temperature should be subsequently lowered so that the substrate temperature decreases to 18°C.
  • Ensure sufficient ventilation during heating and cooling.
  • Turn off the heating 24 hours before the flooring is installed.
  • Install the flooring according to the instructions provided in the packet.
  • Cork grain underlays are not recommended (a possible odour nuisance due to the smell of bitumen).
  • Do not switch on the underfloor heating until at least 24 hours after the flooring has been installed. During the next five days, raise the temperature but make sure that the temperature of wooden flooring never exceeds +25 °C. At this stage, do not even partially cover the floor.
  • The relative humidity of the air must be maintained continuously between 40% and 60%. The recommended room temperature is 18 to 24°C.
  • Moisture changes in the flooring may be exaggerated by exceptional conditions. The manufacturer, seller or installer cannot accept liability for these changes.