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9 Answers

Cold climate (6) standing seam metal roof leak

I have concerns my entire roof is leaking due to improper detailing of my standing seam roof. I also think this discussion could help others who might be thinking of a standing seam metal roof. They are not what they're all cracked up to be. Please look at enclosed photos.

Some details:
I have a shed roof (Structure are I-Joists) with a 3 1/4: 12 pitch. R-60 insulation in cathedral ceiling--"flash and batt." "Flash" is 4-6" closed-cell polyurethane spray foam. Hot roof: Fully Zip taped, Zip sheathing and GAF underlayment. And finally: 1" single-lock standing seam Galvalume.

In Energy efficiency and durability | Asked By David Metzger | Mar 28 15
19 Answers

Fresh air distribution for hydronically heated house?

Currently have a leaky hydronically-heated house.

I plan on removing the siding, installing blueskin VP peel-and-stick, then 2 layers of Roxul R6 ComfortBoard IS from the roof right down to the footings.

Because this should really improve the air leakage, how should I get fresh air in/out of the house to control humidity / air quality / etc?

Do people run a set of air ducts throughout the house from a HRV?

One of the appeals of using hydronic heating is that sound / dust transmission is significantly reduced.

What would you recommend??


In Mechanicals | Asked By John Charlesworth | Mar 26 15
1 Answer

Basement insulation

Hi Everyone-

In the process of having my 1970's basement renovated. Looks like it is simply batt insulation between 2x4's with wood paneling, no drywall. I do not seem to have any moisture intrusion (no stains, mold/mildew smell) but will not know until the paneling comes down and the batt out.

What are my options for insulating this space? I do not want to take down the existing 2x4 frame.


In Energy efficiency and durability | Asked By Mike G | Mar 30 15
7 Answers

Rigid foam roof insulation and polyethylene vapor barrier inside — problem?

Was planning on a r-25 insulated roof deck for a ski house in lower zone 6 NH with cold roof (strapping with plywood) on top of that to help prevent ice dams.
Existing cathedral ceiling is actual 8" rafters framed 24" o.c. with 6" paper faced fiberglass batts. In exploring the original construction (circa 1980) I also found a layer of POLY as an additional vapor barrier....which sabotages my R-25 rigid foam roof plan.....damn.

In GBA Pro help | Asked By Dirk Gently | Mar 27 15
4 Answers

GSHP comparison calculator?

I'm looking for an online tool where I can plug in some basic figures such as EER and COP and compare cost/benefit of two ground source heat pumps. Any ideas? Thanks

In General questions | Asked By C. Maglio | Mar 28 15
0 Answers

New hybrid termite emerges in Florida

Read an article about scientists at the University of Florida discovering a new termite which is a hybrid species formed from the Asian termite and the Formosan subterranean termite. These two non-native species are now mating and have created a "super" termite which grows faster, eats more wood and can handle colder climates.

Not good news since termites already damage 600,000 homes per year in the US and we spend $5 BILLION on damage repair and treatments.

In Energy efficiency and durability | Asked By Peter L | Mar 29 15
2 Answers

How to insulate a condo concrete floor?

My daughter bought a condo in a highrise concrete structure. This past winter the floors have been cold even though the floor is the ceiling of a heated garage (55F) below. The shower floor next to an outer wall was 37F, outside temp was 12F. How can we insulate the shower and bathroom floor? The floor is ceramic tile.
We may even consider insulating the entire condo.

In Energy efficiency and durability | Asked By NORM DITTER | Mar 29 15
11 Answers

Insulating scissor truss

Hi, I am building my first house, what a project that has turned out to be but that's for another day. Anyways, our great room has scissor trusses for a nice pitched ceiling. I would like to have at least 24" of insulation to keep things nice and toasty in the winter. There is a 4' overhang outside on either end. I nailed a 24" high plywood leaving a vent space above where the red is on the layout. My question is what material and how to go about it. To use the high density cellulose is has to be contained by some mesh? Any input appreciated.

In Energy efficiency and durability | Asked By Tom Smith | Jul 19 14
3 Answers

JM Spider overhead

I was planning on using JM Spider on the underside of my structural roof deck. (There is a layer of peel and stick and 5.5" of polyiso foam board above the deck so no worries about vapor permeable insulation inside). The installer is having problems with getting the Spider to stick overhead. The installer says JM changed the fiber recently and they are having difficulties with some wall installations too. While they are working with JM, I was wondering:

Has anyone here had JM Spider installed overhead recently?

In General questions | Asked By Eric West | Mar 27 15
1 Answer

XPS as interior insulation on a plank wall

Architect's plan calls for 2" of "rigid" on interior side of a plank wall in Williamstown Ma (zone 5). Even if we tape the seams and air seal as best as possible, I am still concerned that moist air will get to the back of the planks and create moisture issues. The exterior is not being touched and I assume that there is no kind of air space between the planks and the siding. The space will be air conditioned in the summers and the 2" of xps (class II vapor retarder) gives me some drying capacity to the inside. Is that enough? How risky is the assembly?

In Energy efficiency and durability | Asked By Joseph Carry | Mar 27 15
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