SunTouch’s UnderFloor Retro-fit mats are perfect for adding heat to a finished floor. Designed in both 12" and 16" widths to fit the most common joist bay sizes, they are the only mats of their kind.
A stickler for quality, SunTouch builds their UnderFloor mats using high quality heating wires made with ETFE insulation and oxygen-free copper alloys to prevent corrosion. The end result is a product with the same lifespan as mats installed directly under the tile and which produces almost the same amount of heat (34 BTUs per sq ft compared to 41 BTUS with SunTouch’s TapeMats).
Installing UnderFloor Retro-fit mats is easy. Simply staple the orange mesh on the edges of the mats into the joists so that the mat hangs 2" from the above subfloor. Next install fiberglass or rigid foam board insulation beneath the mat (make sure to use insulation with an R value of NO MORE THAN 19). Do not use spray insulation as it may flow onto the top of the mat or over-expand and push the mat against the subfloor where it could come in contact with nails or screws. Once the mats are installed in the joist bays, have a licensed wire the mats up to a junction box and the box to the floor heating thermostat of your choice.