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4 Answers

We are currently working on two residential projects where we have specified exterior rigid insulation over a 2x6" wood framed wall. Both projects occur within Climate Zone 5 but they also have very different amounts of annual rainfall (260mm in the interior of British Columbia vs 1650mm closer to the coast). The wall assembly looks like the following in both cases with the minor difference of the insulation in the stud cavity.

Exterior Wall Assembly
- Cement Board or Cedar Cladding
- 1/2" Plywood Strapping - Rainscreen

Asked By Brett Sichello | Jul 31 14
37 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
16 Answers

I found that patents exist for products that would use the outgoing heat from a dryer to preheat the incoming air, but I haven't found any thing forsale. I'm not going to get away from using my dryer in the winter, but I'd like to do it as efficiently as possibly. Taking warm air from the laundry room, heating it, and then sending it outside, only to have make up air come from the cold outside seems horribly inefficient. My house is much too humid during the winter to use a dryer diverter and the smell is terrible, so that's not going to work.

Asked By Calum Wilde | Jul 30 14
20 Answers

Hi,

We are building a duplex in Yellowknife, Canada - climate zone 8 (design temp minus 45 - same as Fairbanks).

Our winters are long and dark so some sort of (external) insulated window shutter is a huge energy saving opportunity. Our walls are going to R50, while triple pane windows get about R4.

I'm thinking of using 2-3 inches of Roxul board sandwiched between wood. That could give up to R12.

Asked By Andrew Robinson | Jun 10 14
8 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 [Editor's note: I think David means "rafters"], with the foil facing down between the knee walls. I did plan on filling all voids and foil taping the joints. Then 1/2" sheetrock over the foam. Just want to make sure this isn't considered a double vapor barrier, and if this would be considered good construction.

Asked By david chinn | Jul 27 14
2 Answers

We currently stay in a cottage 3 hours north of Toronto, Canada. The main level of the cottage has standard 2x6 insulated walls. I don't know what the roof insulation is like, but I will find out.
This cottage has so far only been used in the summer, but we plan to stay in it over the winter and want to do some permanent and/or temporary fixes to stay through the harsh Ontario winter in this cottage.
My biggest concerns are:
- only electric baseboard heat available right now, with very high electricity cost here

Asked By Hermann Thoene | Jul 30 14
17 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
2 Answers

The question is when going with foam installation on the attic CEILING between the rafters only not on the attic floor, which is recommended for attic CEILING open or closed cell.

Asked By TERRY KELLEY | Jul 24 14
19 Answers

I am building a home with a conditioned attic. I will be spraying 11-12 inches of open cell foam underneath the roof sheathing. I need to allow the sheathing to breathe to the exterior, for it will not breathe to the interior with the 12 inches of foam. Thus, I was wondering if anyone was aware of a roof underlayment (other than building paper) that is breathable, durable, and that has a high exposure rate.

Asked By JAMES MOYER | Jul 22 09
3 Answers

Which type of spray foam is recommended, open or closed-cell?

I'm about to remove my blown-in insulation out of the attic, and I was trying to figure out which product is recommended -- the open or the closed-cell?

Asked By TERRY KELLEY | Jul 22 14
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