If you have underfloor heating and would like to enjoy the advantages of wood flooring we offer an impressive range of suitable flooring to ensure your designs are not compromised. If you have yet to decide upon an underfloor heating system we can offer advice and provide a solution suitable for your flooring and your environment. The following information is intended as a guide but we would also be pleased to advise you at the showroom or by phone.

Installation of a Floor With Underfloor Heating

We have several floors designed to be compatible with underfloor heating. The majority of these are of an engineered construction which can be floated over a suitable underlay or glued to the sub-floor.

There are many different systems of underfloor heating available on the market, ranging from water fed systems set in concrete or slung between joists to electric matting laid over the sub-floor and beneath the wood floor covering.

It is imperative that the customer obtains full installation and operation instructions from the underfloor heating supplier together with guidance from them regarding the suitability of their product when laid in conjunction with wood flooring.

The most important factor when laying underfloor heating is to ensure that the pipes are set at a consistent level below the floor covering and evenly distributed to avoid heat spots. Heat spots can cause the wood flooring to move exceptionally in those isolated areas. Consequently, as suppliers and/or installers we can take no responsibility for any abnormal movement that may manifest itself at some point in the future.

Prior to installation

The site should be free of all wet trades and the environment compliant with normal living conditions, i.e. humidity should be between 40 – 60% and the temperature should be not exceed 25 degrees centigrade.

It is vital that the sub-floor is uniformly dry and that the heating is fully commissioned at least two weeks before the floor being laid. Concrete screeds take on average one day per mm of thickness to dry in a normally ventilated house but under-floor heating may accelerate this process.

It is important that the heating is started at its minimum setting and that the temperature is increased only gradually to avoid an excessive shrinkage or cracking of the sub-floor. The heating should be increased to maximum operational temperature (but no more than 25 degrees centigrade) by raising the temperature on a daily basis from the minimum level by a maximum of 5 degrees centigrade. The room should be well ventilated and/or a dehumidifier be put in place to allow any excess moisture to be removed from the room. The heating should then be run at the recommended maximum level for several days prior to installation and then prior to installation reduced it to the lowest setting.

Prior to installation of the wooden floor, the sub-floor should measure a maximum of 3% moisture content by weight. The sub-floor provided should be level and this is far easier to manage at the point when the sub-floor is installed. The maximum deviation of +3/-3 over a 3m expanse of flooring is preferable. Should any filling be required at the time the wood flooring is installed, it should be noted that latex is not a levelling compound but will make the surface smooth and free of humps.

Floating installation

When floating the floor, we recommend using Tuplex underlay or a similarly permeable membrane, which allows the heat to be transferred to the wood without hindrance whilst also providing a damp-proof membrane and an element of sound-proofing.

Installation on the sub-floor by gluing

We recommend that the gluing should be done by a professional installer. Glue the boards on the tongue and groove, according to the installation instructions. The boards should then be glued to the sub-floor using a suitable flexible adhesive with a maximum application of 500 grms per m2. Place weights on the floor or pin the boards down where appropriate whilst the glue dries. Pay particular attention to heavy traffic areas.

After the installation

Wait 24 hours before turning the underfloor heating on and raise the temperature slowly from its minimum setting to a maximum of 25 degree centigrade, evenly over a period of at least one week, then reduce the temperature slowly to a comfortable living temperature.

If the wood flooring needs protecting after it is laid, then the covering must be permeable to heat or the heating should be switched off thus avoiding any baking of the floor.

Some seasonal movement in the wooden floor should also be expected, which may lead to gaps appearing between boards when the heating is at its winter setting which should then reduce in size in the summer months when the heating is off or low and humidity is increased. The ambient air humidity must be kept at 40 - 60%. Recommended room temperature is 18 to 24 degrees centigrade. If these conditions are not observed, abnormal movement may occur. The manufacturer, seller or installer cannot accept any responsibility for such occurrences, nor are they covered by the guarantee.

If there are any doubts or you have further questions, please contact your underfloor heating supplier and your wood flooring installer, as the manufacturer of the wood flooring cannot be held responsible for any problems that may occur due to bad site practice.