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5 Answers

Garage mold: cause and design solutions?

I'm in Portland, Oregon, climate zone 4C. Last year we bought an existing house (vintage 1943), with an attached 2-car garage. The garage is unconditioned, uninsulated, and unfinished, with the exception of the wall connecting the garage to the house, which is finished, and presumably insulated. It originally was a 1-car detached garage, but in the late '90s, the previous, long-time owner built a kitchen addition connecting the garage to the house, and also expanded the garage to 2 stalls. The garage roof has ridge venting, as well as a few soffit vents.

In General questions | Asked By Doug Elliott | May 12 15
3 Answers

R-38 ceiling and spray foam

If one sprayed 5" of open cell spray foam on a ceiling area, that would equal to around R-17.5, correct?

Now code requires R-38 minimum for the ceiling in this area. There is no "performance value" of R-38 in 5 inches of open cell spray foam, right?

That would be a marketing line bunch of nonsense as 5" of open cell is R-18 avg. and anyone claiming it is performing like R-38 is lying. How would the code department buy into this nonsense?

In Building Code Questions | Asked By Peter L | May 15 15
5 Answers

How to tie in existing shingled roof when adding exterior foam?

I am adding 4" of rigid foam to my house and am looking for suggestions on how to flash where the adjacent wall ties into existing roof shingles. I am curious if there is a way to put the foam on top of the shingles and then flash. This would, of course, cover the existing step flashing and I am not sure if it is a good idea. My original thought was to remove the shingles close the wall and butt the foam straight to the roof underlayment and redo the connection on the outside of the foam with proper tape, peel and stick, and step flashing. Is there a better way?

In GBA Pro help | Asked By Brian Otten | May 14 15
2 Answers

Basement perimeter wall construction

My basement has a full perimeter sump pump; drainage mat on wall from 1 foot below ground level to loop into the plastic cove that empties to the sump drain below; limestone foundation walls; penetrating sealer on the concrete floor.

I plan on installing light steel perimeter walls where no steel will touch the limestone foundation walls. Closed cell spray foam, treated with a fire barrier, will be installed professionally after plumbing and electrical runs are completed.

In Building Code Questions | Asked By Donna Agah | May 15 15
16 Answers

Non-typical insulation of barn / garage

I live in Interior Alaska Zone 7/8. I have a rather large barn pole barn that needs to be insulated so it can be heated. Since it is rural there is no code but i want to ensure that i do not do something that damages or ruins the building over the long term with that said money is not unlimited. The space is intended to be heated to just above freezing 35 to 40 typical with the ability to warm even more during use. Not a business just personal use during the week.

Barn size is 50x60 with 14 foot walls.

In Energy efficiency and durability | Asked By James Williamson | Mar 22 15
24 Answers

Exposed Wigluv tape

The spec sheet for Siga Wigluv tape claims that it is "UV stable". Does
this imply that it's appropriate for little seal-up jobs on the exterior?
There are a couple of funky end-cap joints on my metal roof which could
let water in if windblown rain arrives horizontally, and I'm thinking
a slap of Wigluv over the slots would be an acceptable fix if it's
likely to last more than a couple of years under sun exposure.

Or are any of these products too new to really know? Did any of the
Siga offerings make it into the "backyard tape test"?


In Green products and materials | Asked By Hobbit | May 9 15
52 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

In Mechanicals | Asked By Justin Fink | Aug 22 13
3 Answers

Poor man's spray foam help

Newbie here:

I am rehabbing a stickbuilt cottage in FL. It was torn back to studs by the previous owner. I obtained permits and am actively getting through the inspections and such. Next step is insulation. I discussed the process of foaming in cut foamboards and the county seemed ok with it. I bought 1 1/2 inch polyiso board from a recycle group that is in great shape. I have close to 200 4' x 8' boards.

In GBA Pro help | Asked By Ferrell Brown | May 14 15
9 Answers

Window replacement

Hi. I need to replace a 5 1/2 foot x 22 inch window in my kitchen . It is 16 years old, has had foggy streaks in it for over 5 years (gets lots of sunlight) and I am told it can't be repaired.
I called two companies to ask for quotes. They replied with quotes over the phone. There was a price difference of over $100.
Turns out one quoted 3 mm thick glass, one quoted 4 mm. thick glass.
Don't they need to know the thickness of my current glass, and match that?

Is there anything else I should specify in the quote? If so, in your view, is it a 'nice to have' or a 'must have'?

In General questions | Asked By Ann Piece | May 14 15
2 Answers

Foamboard and creep deformation

I have been trying to find a way to insulate a brick ledge on the north side of my home. I am planning a large insulation upgrade to help get my floor heat somewhat working and seal up the house some.

In General questions | Asked By Michael McArdle | May 11 15
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