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98 Answers

Unvented slanted roof with radiant cooling and NO polyurethane in 4C

We are in Everett WA, north of Seattle, right on the coast, zone 4C. I hope that our location will save us...
We have a low sloping steel, west facing roof. Double, 30 weight felt paper underneath to dampen rain noise. I presume 1/2" plywood sheathing. 2x12" rafters, 11" true depth.
We will install WarmBoard R (13/16" thick OSB with aluminum tracks) underneath the rafters for summer cooling and supplemental heating in winter.

Asked By Jan Verschuren | Mar 11 15
4 Answers

Intus installation

I am considering Intus windows for a project happening soon due to their great U-value and high SHGC numbers. One thing I'm hung up on is how to install them with a 3/4" strapping rainscreen and exterior trim. The supplier said the window is installed at the sheathing layer then the rainscreen and trim are applied over that. That method seems to flash it well at the top but what about the water running down the face of the windows. There are also weep holes that need to stay open on the bottom making sill trim tricky.

Asked By Caleb Creaven | Jun 3 15
1 Answer

Need input: House location on site, soil compaction, grade changes, retaining wall

I would like your input regarding the house location on my site plan (I am the owner).

My considerations:

1) Southern exposure vs. street angle so we oriented 15 degree from true south. I am happy about this decision and I think the landscape architect is capable to make the landscape work with this orientation.

2) Main unresolved challenge:

Asked By Ying Li | Jun 7 15
6 Answers

Flashing and trim details for doors and no-fin windows with board-and-batten siding over furring and exterior foam board

Hello GBA,
After looking thru a lot of details here, and at FHB and BSC, I haven't found one that's quite right for my situation yet, and I hope you can help me.
I have a garage that was made to look like a small barn (22' x 32', 2 stories, gambrel roof). It was built in the early 1990's, with 2 x 4's 16" on center, 1/2" OSB (plywood at the corners), no insulation, no WRB, and lap siding that seems like particle board with a stamped grain pattern.

Asked By Ben Rush | Jun 6 15
7 Answers

Rainscreen design advice

Did a search on this and came up with nothing... The question centers on a rainscreen design for verticle cypress siding on rigid foam over CMU. Zone 2. Block house. One story.

Thinking 1" rigid foam then horizontal furring topped with a core vent type product then siding.

Interested if this is proper design, if core vent is over or under furring strip and how far apart to place furring strips. Install attaching furring strips over the foam to CMU via tapcons would be a heck of a lot easier with the vent on top of the strips.

Thanks for the time to answer.

Asked By Robert Brown | Jun 7 15
3 Answers

Proposed flat roof design / wall design

Proposed assembly for a heated shed / barn - Worcester MA area

when inside it will have the look of a barn, raw and unfinished - all insulation to the outside.
It is a little outside of the box for most contractors here. Heated

Almost all recycled materials or sourced local, Persist(?) style of Construction -

Roof is tricky - (Flat roof, can buy wedge foam, but cost is unknown))

see pics 30x50

- Truss

- Pine board

- Plywood

- Ice and water to wall assembly (?)

- 8" foam

- Plywood

- Rubber roof

Or should it be this .. 2 adjustments

- Truss

Asked By Howard Kelley | Jun 2 15
2 Answers

Weep screed behind natural stone cladding

I was wondering what if any sort of air space or water run-off space I would need to put behind a natural stone wall. I have read so many different ideas that range from not needing one to needing one.

I live in northeastern Ontario CAD. and our winters can get quite severe. At present I have a natural pine siding on one wall and want to tear it off and apply a natural stone veneer. The stones are directly from the ground and are mostly granite.

Asked By I. Wilson | May 31 15
5 Answers

Perlite in wall cavity recommendations.

I have a 2x4 wall cavity that is only about 5" wide. The cavity contains a steam pipe which is uninsulated. The cavity is obscured by another wall that makes access to it very difficult.

I would like to fill the cavity with perlite to insulate the steam pipe. I can close up the wall to prevent the perlite from leaking out, and have access to the top.

The house was built in 1928. From the outside: brick, air gap, roofing felt, 3/4" tongue and groove.

Asked By Kurt Kiley | May 25 15
6 Answers

Loud popping in ceiling or attic since newer insulation and roof

We live in the northwest. In the winter there is no noise. As soon as it starts to warm up there are very loud popping noises that sound like they are coming from the attic or ceiling. Wondering about heat in the attic. Workers said there is a lot of insulation - not sure what kind.

Any ideas what to investigate?

Asked By M Miles | May 20 15
6 Answers

Exterior foam as WRB

I know this question has been asked so many times and I've done my research but can rigid foam be used as a trusted WRB? Specifically XPS? I am in a cold climate and have read in my research that XPS outperforms polyiso. My original plan was 4" of XPS with house wrap over the foam as I will also be installing new windows which will be "outies". I am just confused if the foam is sufficient with the taped joints or if the house wrap is necessary. So much research has been done but there are mixed results and I want to get right on the first try.

Asked By Brian Otten | May 17 15
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