While not every floor heating project requires an underlayment, they are particularly useful for projects where there is concern about heat loss to the subfloor or when subfloor issues threaten to compromise the integrity of relatively fragile flooring types like tile, marble, or stone.
WarmlyYours offers 3 different underlayment products: Prodeso Cable Installation Membrane, cork, and CeraZorb®.
Selecting the perfect floor heating underlayment will depend on information that is unique to your project like the type of subfloor you're installing over and the flooring type you'll put over the heating system.
The Prodeso Cable Installation Membrane is an uncoupling membrane that can only be used with the TempZone Floor Heating Cable. The membrane provides long lasting uncoupling and crack isolation benefits for tile, marble, and stone floors. The benefit of uncoupling is that it allows for a small degree of foundational movement (which occurs when a house “settles”) without causing the tiles in the floor to crack, break or “pop.” The idea behind crack isolation is that it stops cracks (up to a certain size) in the subfloor from “telegraphing” upwards into the floor which can cause extensive damage. An additional benefit of the membrane is that it can greatly decrease installation time as it allows an installer to complete most residential installations in a single day.
Cork and CeraZorb® are both “insulating” underlayments. Cork is a natural material that is a little thicker than CeraZorb® and is often paired with our Environ floor heating systems. CeraZorb® is a synthetic underlayment that has a higher degree of thermal resistance (R-value of 1.5) than cork. CeraZorb® is also the recommended underlayment for heating on top of a concrete slab and is often paired with our TempZone floor heating products. Both insulating underlayments will also provide some degree of crack isolation benefits.
For more information about how to select an underlayment, check out this helpful post: How to Choose Underlayment
CeraZorb is lightweight—up to 25 times lighter than traditional 1/4" backer board. CeraZorb is a 5 mm. (roughly 3/16 in.) thick, synthetic cork underlayment system that is specifically designed for setting tile and stone and is an excellent insulation choice under our TempZone™ electric radiant floor-heating product.
Recommended when installing your floor heating system over a concrete slab to create a thermal break and increase the energy efficiency of the system.
The Prodeso Cable Installation Membrane is an uncoupling membrane that is designed to be used with TempZone electric floor heating cable. The unique design of the membrane allows for greatly accelerated installations of radiant floor heating—in fact, most floor heating installs with this membrane can be completed in a single day.