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17 Answers

rigid insulation on the exterior of a wall assembly?

Does anyone have experience detailing rigid insulation on the outside of an exterior wall assembly? If so, do you have a solution that locates the rigid outside of the sheathing? I see most of the details here (strategies and details) locate the rigid between the studs and the sheathing. This is a problem for our seismic zone and advanced framing.
Any advice or experience will help!
thanks!

In Green building techniques | Asked By Jennifer Reilly | Feb 26 09
10 Answers

Flashing details

I understand the advantages of using "outsulation" (rigid insulation on the outside)
I am still having trouble finding satisfactory details.
Especially concerning Window head details used with siding.
I went for the pro account here at GBA and started looking at the details.
I still wonder if anyone has actually constructed these details to see what they will look like and how they fit together.
It looks to me like the head details show the water draining behind the window trim(casing) and somehow magically weeping out between the bottom of the casing and the flashing.

In Energy efficiency and durability | Asked By John Brooks | Mar 17 09
4 Answers

Problem with Not to scale Details

I have started looking at the CAD details concerning how the window interfaces with framing and weather barrier.
I downloaded the head sill and jamb details for windows used with siding.
I put them together in a composite drawing(head/jamb/sill) and noticed that the materials and components do not "line-up".
I understand that the drawings are "not to scale" probably in order to exagerate the flashing layers.
Maybe what is needed is one drawing that is to scale and another that illustrates an exploded view to illustrate the layering.

In GBA Pro help | Asked By John Brooks | Mar 18 09
3 Answers

Should I convert my boiler from gas to electric?

My house's heating system is gas-fired hot water. It's a fairly efficient system, but I've been thinking of swapping the boiler out and installing an electric boiler.

Here's my thinking, Electric boilers are more efficient, of course. But they give me more flexibility in the actual "power source." With natural gas, the prices fluctuate during oil crises, and there's only one source for gas in my city.

In Energy efficiency and durability | Asked By Brian Siano | Mar 25 09
1 Answer

This site looks great, how relevant is it to Canadian code and product avaliability?

I live in Calgary, Alberta and am very interested in green building and renovating. As I learn more, I realize that a lot of the information is U.S. specific. Any info would be appreciated.

In General questions | Asked By Colin Hume | Mar 26 09
6 Answers

What kind of exterior rigid insulation should I use?

I am working on a series of small 1950 vintage homes. I am planning on filling the walls with cellulose blown from the outside, adding exterior rigid insulation, and re-siding. The exterior finish is not yet known, but I would like to offer the Architect something that works regardless what is chosen (within reason).

I had been thinking about some kind of un-faced extruded foam (so that I do not add any vapor barriers to the system) but people keep giving me funny looks when I say this.

Any suggestions?

- Ron

In Energy efficiency and durability | Asked By Ron Flax | Mar 23 09
2 Answers

I'm concerned about rigid exterior insulation being a vapor barrier

Hello, sorry to add yet another question about exterior rigid insulation, but I can't find information on this elsewhere. I am working on designing a Habitat for Humanity home in a mixed-humid climate. Dow will give us insulation free, and I want to wrap the home in 1" over the sheathing and building felt, and under cement-board cladding. I am concerned about it being a vapor barrier, however. I can not find perm information for Dow Stryofoam. Any thoughts?

In Green building techniques | Asked By David Quillin | Mar 24 09
5 Answers

Using 1" XPS as the vent baffle

I am thinking of using 1" XPS as a vent baffle in a cathedral ceiling, similar to what is shown here: http://www.clip-vent.com/index.html

I wouldn't actual use that product, but the same idea. I am thinking of spacing the xps 1.5" off of the underside of the roof sheathing, and sealing any gaps with a combination of sprayfoam and tape. The roof would have soffit and ridge vents. The rest of the bay (approx 7") would be insulated with fiberglass bats. I am building in a cold climate, and the space is a conditioned room over an unconditioned garage. The roof is 2x10 stick framed.

In Energy efficiency and durability | Asked By Tobias Richon | Feb 27 09
2 Answers

Insulation achieves its maximum R-value by touching the air barrier on all it surfaces. How much R-value does attic insulation

loose by being open at the top?

In General questions | Asked By terry nordbye | Mar 15 09
10 Answers

any advice about insulating walls in an old house?

i'd like to not have to tear out the interior walls. foam products inserted from the top might expand too fast and not make it to the floor. someone suggested pouring in vermiculite between the studs. i'd really appreciate suggestions/advice. thanks, robin kautzarm@joimail.com

In Green building techniques | Asked By robin kautz | Feb 5 09
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