When radiant-heating cables are installed below the floor surface, SunTouch’s new HeatMatrix uncoupling membrane provides the ability to vary wire spacing. This lets customers fine-tune heat output for a room’s heating needs. And by uncoupling the floor tile from the subfloor, the membrane also reduces the chance that differential movement will crack the tile. It’s installed using a modified thinset. List price is $2.40 per square foot and it comes in a 161-square-foot roll. The manufacturer also sells heating wire with a diameter made specifically for the HeatMatrix. suntouch.com