Q&A: A Forum for Green Building Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


4 Answers

This question is in reference to my attic fan

I have turned my attic fan on several times and now discovered that my fake suede furniture in the den seems to be holding moisture! It is very wet to the touch - like the attic fan pulled the moisture out and everything is now damp - I have no idea what to do!

In General questions | Asked By Marilyn Buice | Nov 3 15
4 Answers

Are there any affordable single home cogen furnaces available?

Just wondering, they were on the news a few years ago, never to be heard from again.

In Green products and materials | Asked By Alan B | Nov 3 15
3 Answers

Roof insulation

The building: 1968 5-plex in Portland, Oregon.
The old roof: tar + gravel, flat.
The new(er) roof: asphalt rolls laid over a slightly built-up frame over the old flat roof. Probably as much as 6-8" between the newer roof sheathing and the old abandoned roof.
The joists: 2x8, 16" O.C., insulated with paper-faced fiberglass (a long time ago, it would appear). Though the walls are to the studs, we have not planned to demo the ceiling, so we're hoping to leave the batts in place.

In Building Code Questions | Asked By jonathan nagar | Oct 26 15
1 Answer

Housewrap and XPS insulation or just XPS on exterior?

Hello,

In General questions | Asked By Joe Roberts | Nov 3 15
6 Answers

Ventilation or no ventilation in spray foam insulated building?

I am planning to use open cell spray foam insulation in my metal building and then build out the interior. I have read two articles by Allision Bailes that seem to contradict one another concerning whether or not a home (or building) that has SPF should be ventilated or not. One article was entitled "Spray Foam Insulated Homes Need Ventilation" Posted on Oct 22 2014 by Allison A. Bailes III, PhD, GBA Advisor on Greenbuldingadvisor.com.

In General questions | Asked By Terry Blackwell | Nov 2 15
3 Answers

Interior foam board vapor barrier help

Trying to use interior foam board between sheetrock and fiberglass batt for bathroom ceiling renovation. Rafters only 3x4, 24+" spacing. Plan on using 2x2 furring strips over 3x4's for sheetrock. Want to use 1.5" foam board between furring strips. Dow recommended to use fiberglass batts WITH vapor barrier, and use unfoiled foam board between fiberglass/vaporbarrier and sheetrock, saying it would not be double vapor barrier as long as foam board is against vapor barrier. I'm not too comfortable with vapor barrier in middle of wall. Bath is high humidity. Any suggestions? Thank you

In Green building techniques | Asked By G J | Nov 3 15
3 Answers

Termites - adding shields to existing house on old stone walls and missing(?) foundation anchors

I'm prepping to dense pack empty cavities on an existing home, and am working from ground up.

Without replacing the sills, how would one go about inserting termite shields on an existing balloon-framed home with a stone foundation?

In Energy efficiency and durability | Asked By Mark Baker | Nov 2 15
7 Answers

Polyiso and WRB questions for old/new home in New England

Hi there-

New to this site- i appreciate the wealth of information.

Thanks in advance for any guidance.

I am preparing to apply cement fiber siding to my under-renovation 2 family home in the Boston area.

Remaining portion of original home is from 1895. first floor consists of true 2 x 4, 7/8" pine sheathing. This portion will get open cell spray foam insulation due to the code requirements (foam will provide R18 out of R19 required)

In Green building techniques | Asked By Frank Mac | Oct 31 15
41 Answers

How is thermal bridging prevented?

The construction process of our home, in southeast Iowa, was completed in January 2014. The house has fiber cement lap board siding and an interior spray foam insulation. In March of 20014 we noticed moisture accumulating, in a vertical line pattern, on the east elevation of the house.

In General questions | Asked By S. Schneider | Oct 5 15
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!