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1 Answer

Anyone have any idea when hyper heat mini-splits that can run multiple indoor units (I need three) on a singly condenser will come to market? Thanks, Dan

I am about to install solar panels at my home. I want to do mini-splits in my house, but because if have a Cape with many small-ish rooms, I would need multiple indoor units. I live in Central VT, so the hyper heat units would be the way to go (it is cold here). However, apparently I can only do one indoor unit per outdoor heat pump on the current hyper technology. I've been told that Mitsubishi has the technology and will release it to the market any day.

In Mechanicals | Asked By DANIEL GOTTSEGEN | Aug 12 14
1 Answer


Client wants to move Hot Tub indoors into it's own 9x9 room. Whole house HRV will be running continuously; I will add dedicated exhaust fan; considering Panasonic Whisper, but have no idea how much ventilation will be needed to exhaust moisture when tub cover is off. Suggestions?

In Energy efficiency and durability | Asked By Bob Irving | Aug 11 14
6 Answers

Best insulation for ventilated crawlspace

For a ventilated crawlspace in a small house near (relatively humid) Asheville, NC, which would be better, Roxul ComfortBatts between the floor joists, or Roxul ComfortBoard nailed to the bottom of the joists, or foil-faced polyiso nailed to the bottom of the joists? Any of these choices would likely be better than the fiberglass batts that are presently hanging at weird angles. I worry about creating an empty cavity if I attach the insulation to the bottom of the joists. I'm not sure I can afford to insulate between the joists and under them.

In Energy efficiency and durability | Asked By Stuart Murray | Aug 8 14
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.

In Energy efficiency and durability | 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

In Energy efficiency and durability | 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.


In Green products and materials | 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.

In Energy efficiency and durability | 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

In Energy efficiency and durability | 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.

In Energy efficiency and durability | 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.


In Green building techniques | Asked By Edward Krause | Aug 8 14
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