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1 Answer

Metal roof and wall assembly in Los Angeles

Could you advise on my roof and wall assembly? I want to do better than code and local building conventions (leaky stucco houses) , but don't want to: (1) waste money since the climate is mild; (2) make inadvertent mistakes by diverting from what's tried and true here, and by indiscriminately applying lessons that are meant for more severe climate.

What's your opinion of the most cost effective spec for this climate?

Asked By Claire L. | May 23 16
15 Answers

Has anyone ever kept sheathing warm and saved labor costs this way?

There are a handful of manufactures who make rigid insulation with OSB bonded to the surface (like a SIP with OSB on one face only. But SIPs are not the topic in this post). This assembly is commonly used for roofing but I was contemplating using it backwards as exterior wall sheathing. By backwards I mean fastening it onto the studs so the OSB is touching the studs and the foam is on the outside. By doing this, the osb is kept warm and that desirable thermal break is incorporated as well (after all thats generally the reason to put rigid on the outer face).

Asked By sean stewart | May 22 16
7 Answers

Fastening details - deck ledger to insulated slab

I am designing an insulated Monolithic Slab. I plan to install 4" of Roxul comfort board beneath and around the perimeter of the slab.

Does anyone have experience attaching a deck ledger to a slab (or stem wall) that is insulated with Roxul? Or is it advisable to place a higher density product beneath the ledger to avoid compression which may happen with the Roxul Comfortboard?

What type of fasteners are recommended for this application? Would a standard wedge type concrete fastener like a red head work?

Other solutions?

Asked By Michael Iacona | May 19 16
1 Answer

Floating slab with frost walls — Plumbing and floor framing

We are doing a relatively large expansion. of a small studio space. A much earlier constructed garage/shed to which the studio space was added on to has been removed. We are using an insulated pad with frostwalls. The expansion will include all plumbing. Due to unavailability of a plumber and concerns over the lack of flexibility of cast in place plumbing, we have decided to frame the 4 x 12 foot portion of the pad.

Asked By Potter Shaw | May 23 16
6 Answers

Installing LP Smartside over 3" foam

Question: I am putting an addition on my house and have a question about fastening the LP Smartside.

My wall details are as follows (from inside to outside).
* 5/8" sheetrock
* 3/4" plywood
* 2x6 wall with r-19 or 21 fiberglass insulation
* 3" foam
* Furring strips, probably 2x4 - has to be at least 1 1/2 thick per LP
* LP Smartside

Asked By brett mattson | May 19 16
9 Answers

Siding butt joints and inside/outside corner flashing

I am installing 3/4" horizontal square edge lap siding using a drainable house wrap rated at 96% drainage without furring strips. I am planning on scarfing butt joints. I do not see the need to use some type of flashing behind the butt joint since the point of the rain screen is to shed water and the flashing would actually seem to interfere with that. Is that correct thinking?

Asked By Scott Smith | May 15 16
4 Answers

Wall design

I am adding a small addition to my house and have been struggling with choosing a wall design. I'm trying to find a balance between efficiency, ease of construction, and cost. I was a fan of double stud walls until I read about potential issues with damp sheathing. It occurred to me at some point that if we ventilate ceiling assemblies, why can't we ventilate a wall? Specifically, I'm thinking about ventilation on the inside of the sheathing in addition to a rain screen on the exterior of the sheathing. Has this already been done?

Asked By Eric Colbeck | May 19 16
4 Answers

Wood stove chimney flashing

Installing wood stove chimney to go through cathedral ceiling with 12/12 pitch. This is new construction. Roofing material will be galvalume R panel. On the roof, what is the recommended layering system to prevent moisture from entering at the chimney penetration? I have seen metal roof with the flexible high temp boots on top sealed with silicone, and I have seen 12/12 metal roof flashing adhered by sealant directly to the roof sheathing with the roof panels cut around the flashing and sealed , and a combination of many other ways.

Asked By Scott Smith | May 16 16
1 Answer

Synthetic underlayment

I have read many posts and articles and believe I know the answer to this question but would just like some confirmation. I am building a cathedral ceiling, vented under the sheathing, and using 24 ga galvalume R panel fastened directly to the sheathing. Since I live in a warm climate, I don't think I should use asphalt felt due to the potential for it to adhere to the metal roof. Does it matter if the synthetic underlayment is breathable since I am venting under the sheathing and if so, what are some recommended products for this use?

Asked By Scott Smith | May 18 16
11 Answers

Revisiting a wall in Climate Zone 5A

Construction is on the horizon in our "pretty good house" in Iowa, Climate zone 5A.

Although I know our wall isn't perfect, we have chosen the materials for a variety of reasons. Currently from exterior to interior we have:
-Hardi-plank siding
-1x4 furring strips for rain screen
-Tyvek WRB
-2" rigid insulation, currently XPS
-Sheathing, currently OSB, taped
-2x6 framing, open cell spray foam in cavity
-drywall, with latex paint

My questions after reading and re-reading the prevailing thoughts on this site are:

Asked By Thomas R | May 10 16
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