Q&A: A Forum for Green Building Experts and Beginners

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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
5 Answers

For a large scissor truss (top chord 31" above bottom chord), we want around R-70 but no more. How do you 'contain' the blown in, or how would you use batts?

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In GBA Pro help | Asked By David A Flannery | Aug 18 14
8 Answers

I want to install a secondary heating system (wood stove primary). Cold climate. What is best ductless heat pump for an open house plan, 2-story?
Are heat pumps better than ETS systems?

thanks,

kelly

In Energy efficiency and durability | Asked By Kelly Mitchell | Aug 16 14
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