Underfloor Heating | Floor Finishes

Floor Finishes
Most floor finishes are able to cope with an underfloor heating system dependant upon whether the underside of the floor is well insulated. Care is required to check the floor finish manufacturer’s maximum temperature limits against the maximum design floor surface temperatures for a given room or space.

Wood, vinyl tiles and plastic floor covering fall into this category whereby the finishes are considered to be hard wearing but in fact are temperature sensitive and consequently considered to have low surface temperature limits. Most fitted carpets can be actually good transmitters of heat, however it is imperative that the underlay is of a waffle type and suitable for Underfloor Heating (UFH) whilst being of a low Tog value.

In refurbishment projects, such as barn conversion which require high heating outputs, greater care is required and hard surfaces such as tiles or stone may be the better chosen options.

	Carpet Most types of carpet can be used with Underfloor heating, although care needs to be taken with regard to the underlay, thermal underlays are not suitable as they do not allow the heat to pass through to heat the room.  Carpets and underlays are measured in Tog values (in the same way as a duvet)  the lower the tog value the easier the heat will pass through, combined Tog values for the underlay and carpet should not exceed 2.5 for your underfloor heating system to work effectively.
	Stone & Ceramic Tiles Most stone tiles, slate and marble, are really good thermal conductors making them a great option for a floor covering over underfloor heating.  Ceramic tiles also work well and allow the heat to pass efficiently through the tile.
	Timber flooring Timber flooring is suitable for use with underfloor heating, indeed the underfloor heating can actually be beneficial to the flooring, without the hot spots from radiators.  Care must be taken to ensure that the timber moisture content does not exceed 10% when the floor is laid to prevent movement in the floor as the timber dries out.
	Laminate flooring A popular choice as the system is easy to lay and allows a good heat output from the floor, engineered timber options are now available to have a real wood finish but without the cost.

The table below summarises acceptable thermal resistances for typical floor finishes adhering to the BS EN 1274 Part 2. Tog value is a textile industry measure of thermal resistance. 1 Tog = 0.10m2 K/W.