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10 Answers

Thermal Bridging

How does one quantify thermal bridging when it comes to the dimensions of the area that is a thermal bridge?

For instance; if there is a concrete area that is 6" wide x 12" tall, how does one calculate that area into the whole R-Value of the structure?

In Energy efficiency and durability | Asked By Peter L | Jun 12 14
2 Answers

Looking for tips on air sealing tub plumbing slab on grade

I am looking for suggestions how to air seal around plumbing rough in for a tub on a slab. Normally we build a 12"x16" 2x box, bring our pvc into the box, usually leaving the pipe long and a little deep in the sand and pour our concrete around the box.

In General questions | Asked By kye ford | Jun 12 14
3 Answers

I am looking for a table about triple-glazed windows prices

Could you please tell me how to get the table? Or do you have a website or link to help me?
My name is Shawn. I am with ABC Acoustics, Inc. in San Diego.

In Green products and materials | Asked By Shawn Sanavi | Jun 12 14
4 Answers

Fiberboard Sheathing for Knee Wall Air Barrier

We live in a cape cod style home and I'd like to install an air barrier on the second floor knee walls. There is bare insulation just hanging between the 2x4's so an air barrier looks to be needed. On one wall that is partially exposed to the outside but mainly in the attic, the original builder used fiberboard. Will fiberboard provide enough of an air barrier or do I need to go to something like OSB? The one area is easily accessible, but the other is through a hatch so the lightweight and easy to cut fiberboard would be preferred.

In Energy efficiency and durability | Asked By HD S | Jun 13 14
2 Answers

To keep basement warm - keep away from heat pump water heater?

We are building an energy efficient home (ACH 0.8 or better at 50 pascals) and I want to avoid a water heater heat pump because I want to put my shop in the basement and I don't want to lower the temperature in the basement. Am I thinking about this issue correctly considering the energy these heat pump water heaters save? We plan on a net zero energy home using solar. stuartkrantz@gmail.com/954-732-3347

In Mechanicals | Asked By Stuart Krantz | Jun 12 14
2 Answers

Is it okay to put an unvented hot roof under a wood shingle roof?

I live on Cape Cod and I would like to put spray foam on the roof and then Sheetrock . There are wood shingles on the roof now and because I am in a historic district I have to keep them. Thank you for your help.

In General questions | Asked By Randy Aubrecht | Jun 12 14
5 Answers

A question, universally...

I apologize if this is a dumb question, I'm kind of a new comer to this site. I haven't really heard anyone mention anything in regards to universal design as it relates to green building. Is it assumed that these principals are already incorporated into your design, or is this just not an appropriate forum for these discussions? Just kind of curious.

In Green building techniques | Asked By Aaron Vander Meulen | Feb 12 11
2 Answers

Where can I get the yellow mesh product in this picture or do you recommend anything else for the air gap?


You quoted an article (Mind the gap eh!) that has this product in it. When I google search, I cannot find it. Can you tell me the name of the product and where to purchase? I am starting my project his Monday.
I am not able to paste the picture here, but here is the link to the article from building science corporation.


Any other recommendations you have would be great. I am a home owner/teacher and these are my summer plans

project plan from inside out:

In Green products and materials | Asked By frost patrick | Jun 12 14
2 Answers

Rockboard [mineral wool] or polyiso?

I'm planning a new house. I've been thinking in terms of 2 3/4" of polyiso on the exterior of the walls. However, I'm now thinking that dense rockwool board *might* be better at least from the standpoint of the wall being able to dry to both the outside & inside. I kinow I'd be giving up some r value, but perhaps I could just up the thickness ? I'm in climate zone 4 Western NC in the mountains. Probably using zip sheating under either insulation board.

In Energy efficiency and durability | Asked By Roy Goodwin | Jun 12 14
12 Answers

Small ducted heat pump?

My wife and I are 69. We're in the process of designing a house for our retirement with our architect. It's going to be a "pretty good house" with a very small heating/cooling load. Neither my wife nor I think the ductless minisplits are all that attractive, AND the air filters would be hard (relatively, because of the height) likewise for the "ducted" minisplits that I've found via Mr Google. ( they're all ceiling mounted and we'd like to avoid having to get on a step ladder to change air filters as we get older & older).

In Mechanicals | Asked By Roy Goodwin | May 29 14
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