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7 Answers

WRB detail with exterior foam and strapping


In GBA Pro help | Asked By Jeff Nelson | Feb 19 13
24 Answers

EPDM gaskets instead of ZIP System?

I was wondering if anyone has tried using EPDM gaskets for air sealing exterior OSB instead of taping the seams? EPDM is cheap, easy, can be put up in the rain, super durable, etc. I am going to lunch or I would explain more of my strategy...

In Energy efficiency and durability | Asked By Spencer Burnfield | Feb 14 13
6 Answers

Flash and batt closed cell with initial flash of open cell

Ok. I'm building an addition. This is in Cape Ann MA. North of Boston. North facing roof 4 pitch that ends in a sidewall. It is a hot roof. it was flashed with 3" of closed cell foam this past october. The foam failed and is now being removed. It pulled away from the roof sheathing and at the rafter tails. Not everywhere, but there Is no Pattern to where it shrank. Some places it shrank 1/8" others 3/4". The installers want to now flash the rafter tails with open cell because they think the sheathing is cold and the open cell will adhere.

In Energy efficiency and durability | Asked By Nick Kent | Feb 22 13
1 Answer

Finding the cold and hot spots in the envelope with an infrared thermometer

I asked a few weeks back for advice on an affordable infrared detector for finding cold spots to pinpoint infiltration problems, heat loss and insulation effects. I found a mid-range infrared thermometer: "IRT207 Heat Seeker." You can pick it up for under $30 at Amazon. I have had mine for two weeks and it is getting a workout as I caulk and seal prior to insulating.



In General questions | Asked By Oak Orchard | Feb 21 13
6 Answers

Rigid board insulation for an unvented cathedral ceiling: fill the void?

Hi there, first post.

I'm building a tiny cabin, Pacific NW, right on the boarder between zone 4/5, 40miles
east of Portland.

I have vaulted ceiling/gable roof. No interior walls in yet.

I have enough rigid board insulation to fill the void (iso). The sheathing was sealed to the rafters with adhesive sealant when laid down. Blocking at the soffets was sealed with silicone. There is rolled mineral roofing over that, all edges sealed with lap cement. All this was done with the anticipation of filling the void with pink fiberglass rolled insulation, with drying to the interior.

In General questions | Asked By Hamlet Jones | Feb 21 13
3 Answers

Joint compound over poured concrete wall

I would like to plaster then texture over old uneven concrete. I saw a product called plaster-weld. Can I use the plaster weld over the poured concrete wall and then just layer on coats of joint compound to get a textured even finish, then seal with a primer and finally paint it? When they formed up the basement walls years and years ago, they weren't concerned with even finish. I can send you a photo if you need one. We get very little moisture in basement. Thank you in advance.


In PassivHaus | Asked By Chris Sutherland | Feb 21 13
12 Answers

Passive house exterior door for reasonable price?

Has anyone come across an exterior door that provides good insulation and beefy frame that's worthy of a super insulated home but comes at a reasonable price? Any suggestions would be appreciated.

In Green products and materials | Asked By Matthew Michaud | Feb 4 13
13 Answers

What is an acceptable air barrier separating showers and tubs as referenced in the 2009 IECC Section 402.4.2.2?

I live in Zone 5 (No.NV) and it has been the local custom to place unfaced batt insulation in outside walls between showers and tubs in new construction. Line item 13 of the referenced Inspection process under the 2009 IECC specifies an air barrier to be used. I'm a certified HERS Rater performing these inspections, but having much resistance to this item.

In Green building techniques | Asked By Leon Mills | Feb 13 13
3 Answers

Unvented rainscreen?

Great website. Thank you! I am building a home on my farm in CA (zone 4B). 2x6 construction on top of a 4-inch concrete slab on pandeck over an ICF daylight basement. Incorporating passive solar concepts, going off grid with a 4400 watt array. Heating with a woodstove in our wet and mild winters (very rarely gets below 20F). Hoping a tight envelope, R-25 walls and an R-36 roof, thermal mass in the slab, and opening all the windows during our generally cool-ish nights will keep us comfortable in our very hot and dry summers (regularly over 100F during the day).

In Green building techniques | Asked By Galen Weston | Feb 19 13
19 Answers

Looking for help designing a durable & efficient wall for a house in the mountains near Asheville NC at 4,000 ft. elevation

I am trying to use articles from this site and from Building Science to design a durable and efficient wall for a residence in the mountains near Asheville NC at 4,000 feet of elevation.

Which would be a better wall; a 12" AAC wall with interior plaster and exterior stucco, or an 8" AAC wall with 3" of closed cell spray foam or XPS sheets on the exterior and then a 1" air/drainage space and then hardiplank? Would the increased complexity and cost of the second option be worth it? Are there any good spacers for the air/drainage plane that are not thermal bridges and will not corrode?

In Energy efficiency and durability | Asked By Stuart Murray | Feb 11 13
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