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1 Answer


Anybody have experience with Henry BlueskinVP? It's a fully adhered WRB and air barrier, but is permeable at 29 perms.

A cursory internet price check reveals it is in the $.50/sq ft range.

Martin mentioned it in Sept, 2010:

Just wondering if anybody has used it and had comments?

In Green products and materials | Asked By Bill Costain | Apr 6 12
18 Answers

HRV vs. ERV vs. Dehumidifier - Unique Situation!

Hi everyone. New member and first-time poser of question. :) Please keep in mind this is FAR from my area of expertise, so talk to me like a dummy; I won't be offended!

I live in Central-Northeast WI, so our annual temps run from about -40 to 90+
depending on the season. The summers overall I'd say are mild, while the
winters are colder than I'd like. :)

I run a home-based business breeding fish and propagating coral and as such,
have a pretty high humidity level (under 90% is pretty rare). I had been
running a dehumidifier in the past but it's recently died on me so it needs

In General questions | Asked By Fred Bocskor | Dec 1 11
2 Answers

Nanawall or La Cantina Folding doors and blower door performance?

I am curious if anyone has experience with blower door performance on a Nanawall or La Cantina folding door system (not as isolated elements, but rather impact, whether good or bad, on whole house blower door performance). I am a builder in Seattle area getting ready to start a new construction project with a number of great energy features including SIP wall and roof assemblies.

In Energy efficiency and durability | Asked By Greg Kruse | Apr 5 12
5 Answers

Using pressure treated plywood on exterior of carriage doors

After reading the article on building carriage doors I would like to build some using that technique but would like a less fancy / expensive approach. There would not be any window required. Could I use ½ inch pressure treat plywood that would be sealed and stained? This would eliminate the meranti trim and cap. It would also be much easier to construct. I am not concerned with insulation as the garage is not heated.

In General questions | Asked By jay mcdonald | Apr 6 12
6 Answers

Closed-cell foam in stud cavities and Tuff-R on sheathing. This going to be a vapor barrier problem.

While residing my house I was planning on using Tuff-R over sheathing. Then in the next year or two I was going to spray closed-cell foam in the stud cavities later on. Or should I go open cell so moisture doesn't get locked in?

In Energy efficiency and durability | Asked By Michael Strid | Apr 5 12
2 Answers

Wish list for the big box stores

Recently a friend who works at Lowes (sponsor of the Builder 20 peer education program that has helped my business immeasurably) asked me a really thought provoking question.

"What do Green Builders wish we had on our shelves that we don't currently stock."

In Green products and materials | Asked By Michael Chandler | Apr 4 12
14 Answers

Does anyone have an appreciable history with installation of horizontal vinyl siding over furring strips, attached through several inches of rigid foam to studs?

I am referring to a general wall assembly with several inches of rigid foam over studs, followed by 1-by or ripped 3/4" ply furring strips attached with headlok screws into studs, say on 16 in. centers--so that there are voids, or vented, areas between strips. How does the siding installation hold up if installed over such strips? Is it good to make the strips wider than, say, 4 inches so the vented areas are less and support for the vinyl is more?

In Green building techniques | Asked By Sonny Chatum | Mar 29 12
11 Answers

Cedar shakes over foam

I am installing cedar shingles on a gable end wall over 1" Dow Styrofoam over Tyvek Drainwrap, over 7/16" OSB. Am I OK to attach the shingles directly against the foam with ring-shank siding nails through the OSB? Is there a better way? I am using premade "panels" of shingles on one gable end and single shingles on the other.
Thanks for any help and advice.

In Energy efficiency and durability | Asked By jpeaton | May 3 10
5 Answers

ERV airflow imbalances

Hey GBA,

Longtime-no-ask-question-to. I hope you are all well.

In Energy efficiency and durability | Asked By Art Vandelay, AIA/LEED AP+, Zone 5 | Apr 4 12
2 Answers

How to properly air seal and insulate a cathedral ceiling composed of structural T&G cedar

This is an existing roof structure currently experiencing moisture problems most likely due to air leakage. This roof is in Winnipeg, Manitoba Canada, a very cold climate. Right now it has approximately 4" of EPS foam and tarpaper. One of the primary reason to address this roof is that there has been significant carpenter ant activity over the last few years. Would air sealing with caulking on the inside be enough of an air seal? (the cedar is the interior finished ceiling as well).

In Energy efficiency and durability | Asked By Jon Fast | Apr 4 12
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