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7 Answers

Roofing Insulation Question

I saw some similar questions, but it is not quite the same. Please help to finalize the design:

The setting: Midwest, low-pitch (2/12) roof with almost no insulation, cathedral ceiling (some roof decking is 2x6 tongue and groove, some is plywood) . We plan to frame a higher pitched roof (6/12) over existing, the newly created attic will be vented and insulated with 2 layers of recycled ISO (total of about 6"). Existing shingles will be stripped to roof decking.

Proposed design (from bottom up):
Old roof decking (T&G or plywood)
1st layers ISO (glued, seams taped)

In Energy efficiency and durability | Asked By Alex L. | Jun 19 10
5 Answers

What is the best way to insulate copper pipes?

Well my furnace died finally and I am replacing it with a Triangle Tube Solo 60. I figure I should insulate the pipes properly and there must be a better way then standard pipe insulation. I am not afraid to invest a little time to do a great job. Please advise and thank you in advance.

In Energy efficiency and durability | Asked By Jeffrey Polchinski | Jun 21 10
0 Answers

Suicide vents not installed in horizon homes in texas

I was cleaning my garage in the evening with the garage doors close... I realized there were no suicide vents installed... is there a code against installing one? It helps ventilate the garage in the summer and cools it in the winter...

In Building Code Questions | Asked By Taslim | Jun 22 10
1 Answer

ThermoMass Foundation

The super-insulated lake cottage I've designed for Chipman Pond in Tinmouth VT includes the ThermoMass insulated concrete system for its walkout basement. This system places the 4" XPS foam board centered within the wall, with 4" of concrete on each side connected by high-tensile fiberglass rods 12" OC. This creates the same strength as an 8" homogeneous concrete wall, but with greater flexibility without cracking, since the moment of inertia and hence the tensile stress within each wythe is reduced.

In Green building techniques | Asked By Robert Riversong | Jun 21 10
0 Answers

Moisture behind Exterior Brick Wall

My 4 story brick wall ( about 40" x 40") was repointed over 7 years ago. I noticed a moldy smell in the top floor and this side wall had bubbles and cracks appearing in the old plaster wall. I took down a portion of the ceiling and side wall. The old plaster lathe boards were moist, some even crumbled. in my hand.

It appears the moisture ventilation system on this wall has been compromised. - it doesn't look like there are any weep holes and the wall is completely capped on top. What can I do to both dry out the existing wall and then make sure it doesn't happen again?

In General questions | Asked By Chris Haun | Jun 21 10
5 Answers

Siding, vapor barrier and insulation

In San Rafael CA (climate zone 16, Sunset Western Garden Book), I will be replacing siding on an ikeler home built around 1960. One story. Currently has the 2-inch vertical siding that I've heard will be hard to find or very expensive. I'm a recently certified green builder and still have a lot to learn — so my question is, what is the best material for the this job? Cost will be critical.

In Energy efficiency and durability | Asked By Jon | May 14 10
3 Answers

Are there any independent reviews for Whole House Fans?

I'm looking for a whole house fan for a 3000 sq ft house. I would like it to have an insulation cap and be as quiet as possible. You recommend the Tamarack line on your site, but I'm looking for more information about brands pros/cons. thanks, Caroline Howell

In Green products and materials | Asked By Caroline Howell | Jan 13 10
1 Answer

Building Science Videos

Here is a link sponsored by the State of Oklahoma

Lots of good videos for all climates INCLUDING Hot/Mixed and Humid
I think all of the videos are over three years old.

I especially like the Joe Lstiburek videos:

and Betsy Pettit videos:

In Energy efficiency and durability | Asked By John Brooks | Jun 16 10
0 Answers

Net Zero in Edmonton

Here is the link to part 1 of six youtube videos that describe what is being learned with the latest and greatest residential housing in one of Canada's coldest climates....10-11000 HDD if I recall correctly. The videos feature Peter Amerongen who is one of the principle designers and the builder involved.

All six videos are there but require a little searching...

In General questions | Asked By Garth Sproule | Jun 17 10
1 Answer

Venting above an Insulated Cathedral Ceiling.

Building with 6" fiberglass insulation in rafter bays in cathedral ceiling on half the the house and 6" fiberglass insulation in the rafter bays PLUS 1.5" ridgid polystyrene pink board on the underside of rafters on the other half. Have had serious problems with ice dams over the years.

Due to storm damage, am going to replace entire roof at this time.

Queation: Would it help to VENT the roof above the insulation, given the different R values of insulation sue to different construction techniques?

In Energy efficiency and durability | Asked By Tom Bickford | Jun 16 10
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