Carpet with underlay floor coverings are used extensively with hydronic underfloor heating throughout Europe, Asia, USA and New Zealand without problems provided the system is designed correctly and simple guidelines are followed.
Most carpet suppliers encourage the use of thicker underlays and carpets to provide increased levels of comfort underfoot. However, the thicker the underlay and carpet the harder it is for the heat to pass through from the heated slab to the room above.
For optimum underfloor heating performance it is better to use a thinner underlay, 7mm is suggested, and to use a typical thickness carpet of around 10mm.
Most wood floor suppliers in New Zealand have an aversion to heated floors that is unfounded. However, there are some suppliers that embrace the technology and offer assistance to customers with heated floor requirements. The fact is that wood floors have movement whether there is underfloor heating or not. Also, the sun coming through windows heats wood floors to a higher temperature than underfloor heating.
There are two main issues to be aware of:
- How much heat will get through the floor?
- Will the timber floor crack or deform when heated?