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4 Answers

Basement & double stud wall concept

Rim joist and floor decks are usually full of thermal bridging & moisture hazards.

In Energy efficiency and durability | Asked By Jerry Liebler | Oct 2 12
2 Answers

'Smart': s-m-r-t...

Hi again. i have heard of OSB panels, et al, as being a 'smart' vapour barrier/retarder in that it becomes more vapour permeable the wetter it gets. assuming 'smart' is a good thing, why is it a good thing that a vapour barrier becomes more permeable the wetter it gets?

In General questions | Asked By erik olofsson | Sep 29 12
8 Answers

Cross Laminated Timber anywhere?

Hi there
Is anybody aware of a US or Canadian manufacturer (not an importer) of cross laminated timber panels? We would love to use them on a few apartment buildings...

In Green products and materials | Asked By sam bargetz | Jun 15 12
0 Answers

Attaching vapor barrier to ye olde stone foundation, oh and there's rats

One of the things I think we don't talk enough about is rodent-proof construction. It's just a skip and a jump away from air-tight construction, and I think we should be marketing and selling this.

Anyway, here is the problem I'm having combining rodent-proofing strategies with air sealing and insulation strategies.

In Energy efficiency and durability | Asked By Stacey Cordeiro | Oct 3 12
4 Answers

Enclosed "3-season" porch in front of 16 foot sliders

Enclosed "3-season" porch in front of 16 foot sliders: Where to put maximum r-value?

In Green building techniques | Asked By Michael Arnold | Oct 2 12
1 Answer

How do you protect from termite or carpenter ant infestation between the sill plate and an ICF basement? I am in zone 7b.

The termites could use the foam as a pathway into the house. Without stripping the foam from the top part of the basement wall, how are the termites forced to the exterior?

In Energy efficiency and durability | Asked By Tadd Wilson | Oct 2 12
7 Answers

Heated Floor Above unheated Garage


Here's a twist to the "How do I prevent a cold floor in the heated room above an unheated garage" line of questions.

I am building a garage in Ottawa Ontario and my builder has proposed an option to insulate and heat that sounds attractive but is apparently difficult to implement.

The ceiling is 16" open web truss system on 16" centers.
There is 5/8 T&G plywood as the top floor substrate.
There are uninsulated 5" ducts flush against the underside of the plywood floor feeding the heated space above.

In General questions | Asked By Gerry Overton | Oct 1 12
6 Answers

Kitchen Remodel in Seattle WA - allowing for make up air with 600 CFM downdraft

I have done much reading and questioning about the code compliance of allowing for make up air and am not clear on viable options in a remodeling situation. The kitchen has attic and crawl space. What might be the most common way to identify the best, economical solution to meeting the 2009 energy code in a remodeling situation?

In Building Code Questions | Asked By april bettinger | Oct 1 12
10 Answers

How to insulate stud walls and roof with OSB-wrapped XPS on outside already in place

We have a new construction garage with living space upstairs (room in attic trusses). We are in zone 4, about 10 miles south of zone 5.

The entire interior will be considered "conditioned space". The roof is metal over underlayment over 7/16 OSB over 2" XPS over 7/16 OSB on trusses. The walls are Hardie Plank over Hardi Wrap over 1/2 plywood over 2" XPS over 7/16 OSB over 2x6 - 24" o.c. studs.

Our insulating contractor has proposed the following:
Exterior walls within living space: R-21 kraft fiberglass.
Exterior walls outside living space: 2" closed-cell foam = R-21.

In Green building techniques | Asked By Ed Barnett | Oct 1 12
5 Answers

Installing Polyiso in attic living space

I am working on a renovation of a 1940's house in Norfolk, VA. I want to properly install the recycled 2.5" polyiso insulation I have in my attic. The attic is used as living space. I have 2 x 6 rafters and want to increase the R value as much as possible by cutting sheets to fit between the rafters and then sealing them with spray foam to replace the R 19 bat that was up there.

In Green building techniques | Asked By Mark Imbrie | Sep 30 12
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