As with tiles, natural stone is particularly well suited to the use of electric underfloor heating as this floor covering can be very cold when not heated. Natural stone coverings are often rather thick so high output heating mats or cables are recommended to ensure a swift warm up time. Heat Mat’s suggested output for these floor coverings is 200W/sqm and thermal insulation boards are always recommended beneath the heating.
An additional consideration with natural stone is in the installation of the stones themselves. As the stones are thick and usually very heavy it is vital to ensure they do not crush the heating cable s during installation. Heat Mat’s recommendation is that the heating mats are covered with a sand cement screed or levelling compound first to ensure that the stones can not damage the heating wires. The stones must then be laid onto a complete bed of sand cement, not spot dabbed, to ensure even heating of the stones themselves.