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2 Answers

Is there a significant advantage to providing more insulation in north facing walls in heating dominated climate zones?

For example n Santa Fe, NM (CZ 5B), where there is a significant heating load during the heating season but very minimal need for space cooling in the cooling season, would the heat loss through north facing walls be reduced enough to warrant adding more insulation to those north facing walls. I believe that may be the case.

Asked By kim shanahan | Aug 9 14
6 Answers

Spray foaming an old, vented attic

I have a few questions about spray foaming my attic. If I decide to move forward, the work will be done by a professional. I'm hoping the folks on this forum who are a lot more knowledgeable than I can help me with my decision.

First, some details:
- House is in Northern NJ (climate zone 6A)
- Built in the mid-1940s
- Stick construction
- Relatively simple gable roof currently covered with asphalt shingles that will probably need to be replaced in the next five years
- The roof stops at the edge of the house - there are no eaves/soffits, and thus no eave/soffit vents

Asked By Matt Culik | Aug 6 14
3 Answers

Roxul vs. Thermafiber?

Anyone know if there a significant difference in quality and/or price between Roxul batts and Thermafiber batts?

I've ordered Roxul Comfortboard (for the exterior of the house) which is being shipped from Ontario to western Wisconsin. I now see it MIGHT be more convenient to source Thermafiber batts (for the interior) in this part of the country.


Asked By Edward Krause | Aug 9 14
1 Answer

Mineral wool boards below grade and termites

My house's structure is made of wood and there are subterranean termites (non-formosan) in my yard and area. I am planning to excavate and insulate the slab perimeter in the interests of saving on heating, but am worried about creating a termite highway.

I figure XPS is right out, and I'm not sure about termite-treated EPS either. The availability, price per R, and ease of installation are attractive, but since the advertised termite resistance just comes from a chemical treatment, I worry that it will fade or leach out over time.

Asked By Nathaniel G | Aug 8 14
9 Answers

Whole home insulation ideas

In addition to my other post I would like to know about the best approach for certain areas of the house here are my concerns

ATTIC: 2" of open cell foam along bottom cord of trusses to seal drywall, also spray foam where top plate and drywall come together, also where insulation baffle meets top plate. 12 inches of blown cellulose on top of the foam
QUESTION: Is this a good plan to seperate the attic from the conditioned part of the house?

BONUS ROOM OVER GARAGE: 3" od open cell in ceiling of garage to keep floor warm

Asked By Anthony Hughes | Aug 8 14
9 Answers

Spray foam roof and vapor barrier

I have a Cape Cod style house that we had the roof sprayed with Open Cell foam. We plan to finish off the upstairs for living space. My question is that If we plan to use liquid vapor Barrier primer/paint do I need to paint all the foam, or can I get by with just spraying the drywall only. Do I need to spray behind the knee walls or will the drywall on the knee walls be sufficient? We do live in central Wisconsin.

Asked By Dave Meyer | Aug 3 14
4 Answers

Detailing bottom of Roxul Comfort board IS

How are those of you using this product detailing the bottom of the wall where the Roxul is exposed?

I noticed on one post about a project in BC, they used a perforated galvanized channel to encase the bottom of the IS. Does anyone know where to source a channel like that?

I'll be using 3" Comfort board over 1/2 CDX sheathing, over 3/4" x 3" furring strips, then cedar shingles.


Asked By Edward Krause | Aug 8 14
2 Answers

Batt insulation for bonus room... installed correctly?

ok. I live in the South (Lower Alabama) and my bonus room above my garage, gets warm during the summer. I went in the attic today to see how the insulation was installed and I noticed that it is Paper towards the room (insulation towards the hot attic space). I read a few articles where basically is states that it doesn't matter (or depends) on which way the paper faces.

Asked By Nathan Jones | Aug 8 14
8 Answers

Buildability vs. durability

I'm going to be building a 28x40 (aprox 1500sf living) chalet style house in upstate NY CZ6 (design temp 6f) it will sit on a walk out basement (one narrow end walk out the rest under ground) I am going to put pex in the slab even though I don't currently plan to ever need it warmer than 55 or so down there.

Been reading on the subject quite a lot, and think that the pretty good house concept you guys have come up with is a great idea, and should get me in a balance point between up front cost, and monthly utility bills.

Asked By Trevor Chadwick | Aug 4 14
12 Answers

Insulation vs. air flow extra expense

Hi, I’m going to have a new house built and am confused on where to spend additional money in regards to insulation and air flow.

I have talked with many builders and most offer a “standard” solution involving fiberglass batts in walls for insulation and no air control layer (other than drywall or caulking holes that they find from blower door testing).
If I am interested in anything better it will cost me more money.

I understand that “batt” insulation can be problematic in regards to having it installed correctly.

Asked By Ani Brown | Aug 6 14
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