Carpeting & Radiant Heat

Scott F. Kelley

In researching the best padding to go on the plywood above staple up radiant heat I have been given many different opinions. One is that the rubber, although relatively low R factor, will break down because of the heating and cooling. "Frothed foam pad" was recommended by the carpet guru but it's tough to find. Then a thin felt pad or a 1/4 inch 8 lb rebonded pad which I feel may be hindering carpet life. Any suggestions?

Rick_8

Carpet & Radiant Heat

We know radiant heat is great for tile/slate flooring. My experience with a 1950s radiant floor with carpeting is that the heat worked really hard and took many hours to heat a room - clearly not very efficient - has anything changed in 45-50 yrs? Considering a MBR/MBath new addition - radiant in tile bath area, hydronic or baseboard in carpeted area?

Steve Bergerson

Carpet is no problem

I have a 3000 sq ft home that is 100% radiant floor heat. Only the kitchen, garage, and entry are not carpeted. My finished basement has no pad and the carpet is glued to the concrete.
My upper floor has 1/2" rubber pad with carpet on top of that.

This is the MOST COMFORTABLE home I have ever lived in. The RFH system works wonderfully with and without carpeting. The catch is that you design the system right in the first place. Your water temp where the carpeting is will obviously have to be higher than where there is no carpeting.

All RFH design programs will help you compute the needed H2O temp, flow rate, and tube spacing depending on your design parameters.

Go For It!!!! and enjoy!

Steve Bergerson

Different carpet pads...

Here are the R values for various carpet paddingin 1/4" Thickness:

1/4" Felt R-1.5
1/4" Hair and Jute R-1.0
1/4" Prime Urethane R-1.0
1/4" Solid Rubber R-0.6
1/4" Waffled Rubber R-0.4

The waffled rubber is more expensive than "regular padding", but for the decreased R-value, I believe it's worth it.

As for the rubber holding up, I talked to someone at Wirsbo, as well as the manufacturer of the padding, and neither has any "red flags" about using this product with radiant floor heat.

The padding people said that the padding is designed to last for the useful life of the carpeting.

Hope this helps

heatboy

What I have found over the years is......

that it can work successfully, if done properly. The normal things apply here, such as output from floor needed, water temperatures, etc. The issues arise around combining carpet and harwood in the same home. Even under the best of circumstances, the carpeted areas will need 15° to 20°+ higher water temperatures than the hardwood areas. My advice, for what you feel it's worth, would be to seperate the floor coverings when you design your water temperature control theme. If running reset, use two seperate mixing systems. One for the carpeted areas and one for the wood flooring. It may cause some manifold and zoning confusion in areas where the carpet and wood floors mix in the same area, but the wood floors will thank you for it since you are not overheating them. While surface temperatures may appear to be the same, getting there with these two distinctly different floor coverings is something that needs to be considered.

If you are bent on using only one mixing system, design it around the wood floors, then add supplemental heat to the carpeted areas with either the same water temperature used in the floors or utilize a second stage from the thermostat with high temp emitters.

hb

To Learn More About This Contractor, Click Here to Visit Their Ad in "Find A Contractor"