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6 Answers

I hate to continue asking what seems to be a different wording of the same question but bare with me. My house is 2x6 exterior walls, 1.5 inch of polyiso rigid fiberglass faced foam outside the sheathing and Tyvek. We are in the 47460 zip.

I would like to know the best way to achieve the tightest wall possible but still allow my sheathing to dry accordingly. 1-2 inches of closed cell in the stud void is something Dana said would be OK, so I am leaning towards that but want to be 100% sure it's OK.

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 20 14
8 Answers

We are doing rigid foam on 4500 sq. ft. of exterior walls at 4" thick and 4500 sq. ft. of roof at 8" thick in a REMOTE application.

We are attempting to find the best value for our exterior foam insulation.

So far the best value ($26 for 2"x4'x8') we could find was NeoPro TK. Seems to be a new product so not a lot of info on this "revolutionary" new material. http://www.permarproducts.com/insulsheathing.html

Our previous first choice was Foamular 250 http://www.foamular.com/foam/products/foamular-250.aspx, until we started getting quotes ($34 for 2"x4'8').

In Green products and materials | Asked By Eric Burhop | Aug 20 14
3 Answers

I am in the process of shopping for window flashing tape and am running in circles about what brand (and type) of flashing tape to purchase. Obviously, price is a consideration, but I do not want to sacrifice quality and longevity.

In GBA Pro help | Asked By Matthew Michaud | Aug 20 14
7 Answers

From all the reading I have done, am I correct that I don't want to use closed-cell and need to use open-cell spray foam in the band areas of floor joists of the basement to 1st and 1st to 2nd floor areas when I have used polyiso sheathing on the outside of the walls?

I believe that is correct because of the perm is so low for the polyiso and you don't want to use another very low-perm product like closed-cell spray foam sandwiching the Zip wall sheathing. I'm just confirming if I read everything correctly.

In Energy efficiency and durability | Asked By john bell | Sep 19 12
1 Answer

I have an attic above my kitchen with 3 interior walls and I am trying to figure out how to insulate it correctly.

Currently the walls facing the bedroom and the entry way have fiberglass insulation.
The floor has cellulose insulation. ~2-3 inches.
The ceiling rafters has ~4" of white fiberglass/denim insulation inside of perforated plastic bags between the ceiling rafters, this appears to be pretty consistent, but I suspect it is leaking a bunch of air.

The roof line is several inches about the existing insulation and connects to the space above living rooms vaulted ceiling.

In General questions | Asked By John Reuter | Aug 20 14
8 Answers

I am preparing my attic for some additional insulation and was wondering what the consensus is on this subject. I currently have a fair amount of plywood flooring in my attic, installed over R19 fiberglass batts that were laid in between 2X6 ceiling joists. The batts are faced, installed with the paper side down (towards the ceiling sheetrock). I was planning to blow cellulose over these floored areas, leaving the plywood in place, but I thought I better be sure there wouldn't be issues with moisture, etc. Does the plywood need to come up or can I go over it with the celullose?

In General questions | Asked By Tommy Detamore | Aug 19 14
6 Answers

Is the technique easy to learn? How many shims crews would you use on a window?

In General questions | Asked By David A Flannery | Aug 18 14
13 Answers

New construction, zone 4 on the line of zone 5 (47460).

Bonus room over garage with radiant floor heat in concrete floor.

My floor system has some areas that are blocked off with framing to add support to the ends of the floor in the bonus room. What can I do to insulate those blocked off areas before the ceiling goes in? Would 3.5" of open-cell be enough tot help with keeping the bonus room warm or would it completely block any benefit of migrating warm air from the below garage floor?

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 18 14
3 Answers

Having IAQ problems with a 5 year old home on the coast in South Carolina. We had the attic foamed with Demilec Open Cell Foam and crawl space done with closed cell a few months after we moved in. Blower door tests performed after the foaming (forgot the #) revealed the home is very tight, and in summer months we are experiencing the "Fishy" odor when the sun beats on the house and the AC is running on the second floor, first floor not too bad, also not too bad during the winter.

In General questions | Asked By Tom Oelschlager | Aug 19 14
12 Answers

New construction zone 4 on the line with zone 5 (47460)

Bonus room over garage with radiant floor heat in garage floor

2x12 bottom cord in the floor and 2x8 rafters.

I plan to pre-hang drywall on the knee wall in the bonus room and spray 3.5 inches of open cell foam in between those studs. Then I plan to install 1.5 inch fiberglass faced PolyIso rigid foam on the attic side of the knee wall and tape the seams.

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 18 14
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