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2 Answers

Does anyone know where in Western Washington I can buy Timbersil to make raised beds in my garden?

In Green products and materials | Asked By Bonnie Moonchild | Jun 5 11
1 Answer

Is it possible or even a good idea to use rigid foam ,(xps or poly iso ) under the drywall on a vaulted ceiling.The house is in zone 5 with sissor trusses in this area. Above the ceiling is R38 fiberglass with venting at the soffits and ridge.The ceiling would then be refinished with drywall or wood paneling.

In GBA Pro help | Asked By David Gervais | Jun 5 11
5 Answers

We have a family room with a cathedral ceiling which gets very hot in the summer. Bay Area climate 3C. The cathedral ceiling has 2x6 rafters with plywood sheathing/asphalt roof on top, drywall on bottom. I removed the eave blocking and pulled out the fiberglass batts which were original insulation.

The cavities are 8 feet long by 22" wide by 5" tall and accessible from the both the attic (top of cavity) and the outside (bottom of cavity via removed eave blocking).

In General questions | Asked By Harlan Lau | Jun 4 11
1 Answer

Here's a link to Ted Cushman's article on Dan Kolbert's latest project -- a zero-energy house in Maine: Playing Offense on Energy

Thanks to Allan Edwards, who posted the link on the JLC forum. Good work, Dan -- keep it up.

In Energy efficiency and durability | Asked By Martin Holladay | Jun 3 11
19 Answers

We are preparing to build a 12k sf building. Wood framing, all corrugated metal sheeting. Some builders have recommended low E sheeting products to trap between the framing and metal sheeting to supposedly achieve an R15 or so. The physics of this just does not make any sense. Because the building will be climate controlled, 24/7, we are further looking to install 8" batts in the walls and ceiling throughout but that only gets me to an R25-30 in the ceiling in which we would like to see an R40 in the ceiling.

In Green products and materials | Asked By bob smith | Jun 3 11
3 Answers

Hello GBA

I’m in the process of planning a new home for my wife and I in the Pacific Northwest (4C climate zone), is there any reason besides durability to pour a concrete floor in the crawlspace?
This will be a conditioned space, foundation will be ICF’s with all the waterproofing details intact, just seems like a lot of $$ and energy to pour a slab that will see little use. I may be down there twice a year to change the filters in a couple of pieces of equipment, but it won’t be used for storage or much else.

In Energy efficiency and durability | Asked By Duane Brooks | Jun 3 11
3 Answers

I am going to lift a concrete patio slab that has a negative slope towards the house!, maybe at about -2 degrees. this is creating a big drainage problem.

Generally, there are two options for slab-jacking
1. a grouting method, where cementicious material is pumped under the concrete. weight -> 100-150 per cubic foot
2. a polyurethane method of injection that cures when it expands. that weighs far less -> 4-8 pounds per cubic foot.
weight is a concern because of resettling.

In Green building techniques | Asked By gramps888 noname | Jun 3 11
26 Answers

I am building a home with a large amount of steel beam cantilevers to the outside of the structure. I am worried about thermal bridges to the inside of the home, condensation, etc.

Directly against the web of the beam would be placed the sheathing, and then the siding (stucco). Directly below the flange would be a stucco board and then stucco.

Since both the web and flange are right next to the exterior, what is the best method of insulating? I was thinking of filing the web with rigid, foam, or wool, and then applying a Dow insulated sheathing (R-3 to R-5).

In Green building techniques | Asked By Brandon Mullenberg | May 31 11
10 Answers

I spent the last 45 minutes reading a spirited debate regarding fiberglass vs bubble wrap. If, however, my major concern is to stop condensation with the least chance of mold, should I use foil-bubble wrap? I live in central Virginia. The duct in question is in the ceiling of an unfinished, air conditioned basement and is the supply for the upstairs heat pump system (Basement has its own system.) I'm running a dehumidifier (45). Thanks

In General questions | Asked By Michael Mathieu | May 31 11
0 Answers

Dr. Feist awarded the PassivHaus Pioneer award to Amory Lovins to kick start a new tradition to honor the influential individuals who pushed our understanding of efficiency in buildings at this year's 15th annual international PassivHaus conference at Innsbruck in Austria. He outlined briefly his early thoughts about Amory's visionary book "Soft Energy Paths (1979)" and pointed out that it took him a while to realize that Amory really was right on the mark with his assessment that we need to shot for nothing less than 80-90% increase in efficiency. So very true!

In PassivHaus | Asked By Thorsten Chlupp | Jun 1 11
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