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2 Answers

My 1907 house has 2" x 4" rafters on 34" centers. After stripping to roof to the original 1 x 4 skip sheathing, I am planning to add 6" of polyiso foam and then a layer of plywood sheathing. The scrap rate is high if I have to cut every sheet to 48 x 70". Is there a precedent for using tongue and groove roof sheathing (assuming I can find it locally) without the seams landing on the rafters in this sort of application?

Asked By Keith Richtman | Jul 29 14
10 Answers

We're about to begin framing on a new house in zone 6A (Minneapolis). From months of reading and following posts here, I've devised what I think is a wall/insulation strategy that will work. Does this look right, or are there any tweaks that could make it:
a) perform better (within reason; we're going after the "pretty good" model, not a Passivhaus)
b) more cost-effective
c) easier to build

The concept (inside to out):
- Drywall
- 2x6 stud wall
- Membrain or similar (6-mil poly if the inspector insists...sigh)
- 5.5" blown fiberglass cavity insulation (BIBS) = R-23

Asked By Joshua Wyatt | Jul 28 14
5 Answers

Looking for an answer before I start this project. I live in northern MN. I had my attic spray foamed 4" behind knee walls, 3" in the living space. This is a 1 1/2 story with a non-vented roof. I want to know if its O.K. to use foil faced 1" rigid sheets to cover studs, foil facing down between the knee walls. I did plan on filling all voids and foil taping the joins. Then 1/2 sheet rock over the foam. Just want to make sure this isn't considered a double vapor barrier, and if this would be considered good construction.

Thanks

Asked By david chinn | Jul 27 14
5 Answers

Hi Guys,

So after getting a $310 bill from the folks at Duke Energy last month, I decided it was time to figure out a more efficient way to cool our home. I've since asked them for their free energy audit to identify areas where I can save energy.

Asked By Jeff Lever | Jul 29 14
4 Answers

11' X 30' room. Fujitsu 9rls2h. The specifications shows the flow pattern is long and skinny. Would it be best to install at the middle of the long wall or install at the end on a short wall? There will be ceiling fans at the midpoint and at the point farthest from the minisplit if on a short wall.

Asked By Shawn Shumaker | Jul 28 14
2 Answers

A major source of heat loss/gain are the side east and west facing plaster & lathe side walls.

I've measured the temperature of those walls; they stay hotter than outside temps well into the night, and there's 5-10 degree increase as you go up the wall from floor to ceiling. They're actually hotter than ceiling and kneewalls alot of the time. There's also some moisture coming through; the plaster is rotted through under the window apron and there are cracks in the corners.

Asked By Tomas Bridle | Jul 28 14
8 Answers

Hello, I really appreciate this website.

I understand that powered attic ventilators have a lot of problems. But my contractor is suggesting adding one to support a whole-house fan, due to the limited attic ventilation. (I do have some passive ventilation but not quite enough, and the gables are maxed out because it's a flat roof.)

So as long as I always run both fans at the same time, and as long as the cfm of the whole house fan exceeds the cfm of the attic fan, is there still going to be a problem?

Thanks!

Asked By Robert Shelton | Jul 25 14
34 Answers

Hello folks,

First, I'd just like to say how thankful I am for the invaluable resource that is GBA. I spend A LOT of time reading the blogs and Q&A and I find that pretty much any question I might have has been covered here already. Though sometimes my understanding gets a little vague regarding certain details so I am hoping for some input on a potential wall detail.

Asked By Noah Byler | Jul 23 14
3 Answers

I am planning a 30'x22' farm workshop in Eastern Ontario, Canada. I want to end up with a level floor suitable for woodworking machines (table and bandsaws, planer, jointer etc) , Floor will be on grade, location is on a small rise and I will make sure there is good drainage away from building. I will place 2" of SM insulation under floor. I will most likely frame double stud walls and insulate with 6" to 7" of Roxul.

Asked By mark godfrey | Jul 26 14
10 Answers

Reading about rainscreen siding systems it seems that the recommended gaps are typically 1/2" to 3/4" between the housewrap and and the back of the siding. Is there any reason why one couldn't do a very large gap using thicker furring material? Maybe around 3" or 4" between the siding and the sheathing for architectural reasons on a remodel? Would there be problems with having that large of a gap?

Asked By Kevin Hardy | Jul 26 14
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