Wood – install wide-plank solid hardwood over radiant floor heat

hardwood-floorradiant-heating

I've been planning to replace my living room carpet with hardwood. I have radiant heating under the floor (boiler and pex piping). I was originally looking at 3/4" thick 3" to 5" wide boards, but after looking into how to DIY, I ended up with more questions than answers.

The recommended method of installation is nailing, but I have radiant heat, that sounds like a bad idea. Other advice I found recommended not to glue or float the boards. I'm in a cold climate as well, and saw advice not to use wide boards because they would warp. Is it really a good idea to put hardwood over radiant heat? And if so, what's the recommended method of installing it?

I used to have engineered beech (plywood backing) in my 2nd floor bathroom which was floating and the boards were glued to each other, and it held up well for over 10 years aside from water damage around the shower. I have laminate in one room and it was ruined when the roof leaked while we were on vacation (ice dam that formed in a spot that had never leaked before), so I'm not fond of anything that is MDF backed. I have pets and kids so its possible liquids could sit unnoticed on the floor.

I ordered various samples of solids and engineered woods. To my horror, some of the samples of engineered hardwood were MDF backed, and the 5" wide 1/2" thick plywood backed samples were slightly warped.

Whatever I install, I want it to last. Can I go with 3" hardwood and short nails or glue the boards together and float it? Or is engineered really the best way to go?

Best Answer

There are lots of resources covering this topic, and since your question is rather broad I'm inclined to refer mostly to them. In general, you can install hardwood over floor heat if:

  • Subfloor temperatures are reasonable (say within 15 degrees of room air temperature)
  • You stick to quartersawn wood species that are known to handle heat well, or
  • You go with an engineered floor

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