What types of flooring can be used with electric radiant heat?

Question

I am considering converting an old enclosed sleeping porch into a usable room year round (in Ohio). Currently the floor is a big slope to allow for drainage when it was still open, obviously I want to level the floor but was considering installing electric radiant heat in the floor at the same time because there is no heat in this room yet.

What types of flooring materials work with electric radiant heat installed on a floor with wood joists (not a concrete pad)?

I know tile is the standard choice that works well, however I am concerned that there may be some movement in this floor because it is an old porch and I don't want the tile to crack.

PS - I ask because I am in the position to install it if it would work well. If it looks like it does not make sense on non-tile floors I may just install a small electric baseboard heater.

Answer 1

Radiant floor sellers will tell you that their systems work with any type of floor.

Contractors that do repairs will tell you stories of floors gone bad over radiant heat, like hardwood that warps or laminate that delaminates.

I will tell you that the performance of the system will be affected by the insulation value of the floor covering. Carpet will hold some of the heat out, wasting some energy. But exactly how much, and whether it will be enough to matter, are very specific to each situation, so I can't guess.

Answer 2

Some electric radiant systems can be used with laminate floors, e.g. http://www.suntouch.com/mats/, or even floating/engineered wood floors according to http://www.thermosoft.com/radiant-floor-heat/ .

Laminate might be a good option as it can flex and is easy to install. Check with the radiant heating manufacturer to ensure you're using a flooring and adhesive that are compatible with the floor heat, but I doubt the temperature will be a problem -- radiant floor heat probably doesn't get much hotter than your floor would naturally get on a hot summer's day with the windows open.

Answer 3

Wood is OK - we have underfloor heating installed in the top two floors of our Victorian house. It's a water based system with pipes and heat spreaders installed just below the floor boards.

It's not as efficient as tile, but does heat the rooms quite nicely.

With new wood you'll find that it shrinks quite considerably as it dried out more quickly than you'd normally expect. So I'd recommend screwing it down and then relaying it 6 months to a year later to tighten up the joints again.

Answer 4

I don't have detailed knowledge on this, so I'll defer to the other experts here. However, I would get the specifics for the radiant heating system you are thinking of installing, specifically the maximum temperature that it can reach. Then just double check any flooring you plan to install for any limitations, e.g. some glues may release above a certain point. I've seen similar systems (water tubing based) installed under carpeting, though if there is any moisture potential, you would want to avoid that since heat and moisture will result in mold.