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14 Answers

Is there an alternative to the under-slab rigid insulation system in passive house design?

I think I saw a detail somewhere showing an insulated suspended floor over a crawl space in lieu of the slab on rigid normally used.

In Green building techniques | Asked By Janet Digby | Nov 2 12
3 Answers

GU24 base CFL?

I have just had a home built that is an energy efficient home. All the light fixtures are designed to take gu24 CFL's. After three days the first CFL blew the second within a week the third just blew and we have not been in the home a month. I had a electrician check the voltage and earth to the CFL ha says there is no problem with the wiring.

In Green products and materials | Asked By Rev.Alan Perry | Nov 2 12
7 Answers

Is my slab at risk left unheated through the winter?

I had grand plans for getting my garage closed in, and the rough mechanicals installed before winter. Life (uh... work, actually...) intervened.

I live in MN zone 6, and am building on alluvial sand from the Mississippi River. I built a block stem well on poured footings four feet deep (below frost line), 12 inches of compacted sand was placed on top of undisturbed sandy soil.

In General questions | Asked By Kent Jeffery | Nov 7 12
10 Answers

Condensation on Windows in a 105 Degree Heated Room

Hoping some building science folks might have some good suggestions. I'm helping a contractor friend build out a yoga studio in a commercial space. The yoga that's going to be practiced there is hot yoga, more specifically Bikram which calls for a room temperature of 105 degrees (yes, you read that correctly. I actually practice Bikram and it's pretty great).

In Energy efficiency and durability | Asked By Chris Ermides | Nov 7 12
12 Answers

Best details for thin stone veneer exterior wall

We are renovating part of our exterior and will clad it with thin stone veneer. However, the more I read, the more confused I am in determining the best exterior wall construct. We would like to add 1.5 inch of insulation to the exterior in order to eliminate any thermal bridges (placing all insulation to the exterior is not an option at this point due to design decisions along the way). The needed wall construct seems complicated and expensive and would like some advice on how to simplify it.

exterior to interior construct in toronto or zone 5.

stone veneer

In Energy efficiency and durability | Asked By christine charette | Nov 7 12
4 Answers

Metal roof with exterior fasteners OK for school?

My school board is discussing a new roof for our building. We recently insulated our attic space and want to prevent any possible ice dam water infilitration with our new roof.

In Energy efficiency and durability | Asked By Adrienne Raymond | Nov 7 12
6 Answers

Basement Finishing

I am building a new home in zone 4, Shelbyville, Kentucky. This is my house plan:
http://houseplans.co/house-plans/1236/

In General questions | Asked By Aron Robinson | Nov 6 12
15 Answers

Housewraps, cedar siding and moisture on interior of exterior wall

We built a Timberframe home in 2002. This past winter we noticed that we had moisture on the inside of our exterior sheeting. I have read many articles and have received a lot of opinions. However, depending on who I talk with, the answers are different. 1) We put cedar siding over Dow weathermate housewrap without a rainscreen. This seems to be the majority of the problem. 2) one solution was to remove the siding and put 1 1/2 rigid foam insulation, a rainscreen and then the siding. The idea here is to move the duepoint away from the walls.

In General questions | Asked By Tom Wilson | Oct 8 12
9 Answers

Mixing cellulose insulation and whole-house fan

Had 6" blown cellulose added to our small 440-sf attic in spring 2010 (entire upstairs is 900 sf and balance of area beyond 440 sf is cathedral ceiling) ... The contractor installed a rigid insulation dam around the small whole-house fan (Tamarack 1600 Gold with 1150 cfm on low speed, we only use low and never high due to fan noise) ...

In GBA Pro help | Asked By Bruce Sanford | Nov 6 12
2 Answers

Gaulhofer windows

We are window shopping, so to speak, and are leaning toward buying Gaulhofer windows. Does anyone have experience with this type of window? We are also interested in Thermotech and Fibertech, and they offer some great options for low iron, low u-value windows. Any opinions on which window YOU would purchase (and why) would be appreciated!

In Energy efficiency and durability | Asked By jessie pratt | Nov 7 12
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