0 Helpful?

I am working on a single family house in Climate Zone 5 in New York State.

The first floor is a suspended concrete slab with radiant heat over wood framing. The basement is totally buried with the exception of the top 6". It's covered in 2" of rigid insulation. It will be heated but to a lower temperature than the first floor.The only opening into the basement is a bilco door.

I had originally specified 1" white Dow to be used under the first floor joists but am wondering if I can specify instead one of the radiant barrier materials in the interests of economy. Thanks.

Asked by Linda Gatter
Posted Feb 7, 2013 5:08 PM ET

Tags:

2 Answers

Select your preferred way to display the comments and click "Save settings" to activate your changes.
1.

Linda,
If you install a radiant barrier instead of insulation, there will be more heat flow from the heated floor into your basement. Unless the basement is finished space -- and it doesn't sound like it is -- you probably don't want downward heat flow. So I advise that you install a layer of insulation.

If you want the best of both worlds, install a layer of foil-faced polyisocyanurate. Two inches would be better than 1 inch. The foil facing is a radiant barrier.

Make sure to install the rigid foam in an airtight manner. Tape the seams of the rigid foam with a high quality tape.

Incidentally, foil-faced polyisocyanurate is much easier to tape than white EPS foam.

Answered by Martin Holladay
Posted Feb 8, 2013 8:27 AM ET

2.

Thanks......I meant to say 1" Thermax, which is polyiso. Sounds like I should stick with that and increase the thickness.

Answered by Linda Gatter
Posted Feb 8, 2013 10:39 AM ET

Other Questions in Energy efficiency and durability

Best method for air sealing an existing tongue-and-groove (wood) ceiling? Sheetrock is out.

In General questions | Asked by Greenconfusion | Apr 13, 17

Ventilation - Ridge Vent / Soffit / Gable

In Energy efficiency and durability | Asked by bhsizemo11 | Jul 28, 17

Trying not to over-ventilate attic with continuous soffit board?

In Green building techniques | Asked by Inger Peters | Jul 28, 17

Hardwood floor in basement on concrete - new house

In General questions | Asked by MillerConstr | Jul 27, 17

Choosing between Mitsu and Fujitsu mini split, need advice

In Energy efficiency and durability | Asked by maquino | Jul 27, 17
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!