radiant floor heat w/ plank flooring
I would like to install a radiant floor heating system in the basement of a 150 year old house. I am pouring a new slab in the basement. I want to use recycled wood planking for the new finished floor. What would be the best way to execute this. In the slab or use sleepers and plywood above new slab so wood plank flooring could be nailed to sleepers. thanks
Replies
First. I know only what I have read about RHF, so this comment is just a WAG.
If you are pouring a new floor with RH in it, the net effect of the heat will be less with sleepers and a wood floor above it.
The latest issue of FHB has an article on RHF for wood floors in it. Worth the price if you don't already have the subscription.
My suggestion would be to go ahead and repour the floor if it realy needs it. Being sure to add 2" of rigid foam under the slab for insulation. Then put the radiant heat in using the system decrbe in FHB.
Remember, I don't know first hand that this would be best, but seems logical to me.
Others may offer better advice based on real world experiences.
Dave
The owner wants to match the existing 3/4" wide plank flooring upstairs in the old house. I am planning on doing a poly vapor barrier, 2" rigid foam, wire mesh, pex tubing, 2 x 4 sleepers embeded into the concrete, 3/4" plywood sub floor and then nail the plank flooring to the plywood at the location of the sleepers. I tried to talk the owner into a pre-engineered floor but he wants the old look of the wide planks. I figured this would give him the best floor. It may take a little longer to heat the mass but because there is no air space between any of the layers, I thought that this would create the tightest floor, or mass.thanks
Your plan sounds good. You are right that an engineered wood-look (e.g. Pergo) floor would work better for the heating system. Less insulation above the slab is always better than thick layers of wood or carpet.One saving grace is that it is a basement. Therefore "ambient" (soil) temperature on the other side of the walls is very constant. And solar input, being absent, doesn't vary. Those variables can haunt a high-mass, well-insulated RFH system above ground. But in a basement, you'll get decent performance regarding holding a set-point even with the high mass and wood flooring. Still, I'd keep the total wood thickness to a minimum. Nailing onto enbedded sleepers being better than one layer of plywood which is better than two layers of plywood. I would never leave an air space (sleepers on top of slab).David Thomas Overlooking Cook Inlet in Kenai, Alaska
After reading your details, I would follow David Thomas's advice.
Still get issue #168 of Fine Home Building. There is a caution in one of the side bars of the RHF atricle about hardwood floors reacting to the heat. I think the author termed it shock, that could cause to much movement in wood floors.
Agian, just what I have read. Not what I know from experience.
Dave