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

[Click map to enlarge]

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

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!


14 Answers

Need condensation control — Want a bath vent without another 4" hole outside

Any brainstorming helps.
Have "sealed" window in bath anyway but do not want to open in winter north Iowa.
Radon vent (other side house) condensates.
So I don't want to make another 4" hole for bath vent.
When I turn on radon fan I hear water slosh down in pipe that's horizontal.
And dryer is another 3" hole. That condensates too. (I tried manual fix. See pics.)
And vent stack is another 4" hole.
And gas water heater is another 3" hole out chimney.
And water pipe is another.

Asked By Charlie Darwin | Apr 30 15
1 Answer

Skip the plywood, go right ot the Comfortboard IS

I live in central Vermont, heating zone 6, hoping to get a little bit of feedback on the wall system I have in mind for a 4 season workshop (barn), with small efficiency apartment on the second floor.

Asked By Blake Olson | May 2 15
1 Answer

Need help puzzling through the details of outfitting my house with a mini-split system

Right now my house has a 19 year old 125,000 BTU 80% efficiency gas furnace with ducts in the unconditioned attic, partially buried under insulation. I'd like some help determining if mini-split heat pumps will work as replacements, and in what configuration.

Asked By Nathaniel G | May 2 15
0 Answers

How can I seal this space w/ moisture in mind?

Hi All,

I am working on renovating our second floor which includes putting in a master bathroom and gutting and redoing an existing 2nd floor bath. It is a 1952 cape with brick siding on concrete block. The masonry walls are completely uninsulated in most cases. I have taken advice from the GBA site while researching various issues associated with this project and figured this would be a good place to ask about this.

Asked By G S | May 2 15
13 Answers

Repairing notched bottom plate and floor joist

I am moving a cold air return before I insulate my home and as the title suggests, I'm looking for some advice "repairing" some of the notches.

Asked By Nathan Schulte | Apr 29 15
1 Answer

Small spots on inside of Weathershield double pane windows with argon gas

I purchased and installed vinyl clad Weathershield windows. They are showing spots on the inside of the window panes. Has this window failed or is this the result of the argon gas failing. I notice them at the bottom few inches. I am attempting to sell my home and buyers are concerned at what might be going on. They will rely on your opinion.

thank you, Gene.

Asked By Gene Schiferl | May 1 15
2 Answers

Did I build my roof incorrectly?

I am the Owner/ GC for my house. I also live outside of Austin, Texas. I directed my roofer to overlay the outside OSB decking, with StormShield, an adhesive water barrier, instead of felt. On the inside of the roof, I had Open-Cell foam sprayed 6 inches thick, and sealed the inside of the attic space.
When you look at my house from the outside, it's possible to see the 'outline' of the attic area. It's as if there is a visible temperature variation apparent, from the insulated portion of the house, than from areas where the spray foam is absent (like the garage).

Asked By STEPHEN VENSKI | Apr 30 15
3 Answers

Sealing around fire sprinklers in cathedral ceiling

I have a vaulted, insulated, cathedral ceiling in warm California (zone 3) and code required firesprinklers for my tiny guest house (5 total). My piping and sprinkler heads are installed in the center of my 2x12 bays, which will be filled with R-38 fiberglass batts. I have another R-18 of rigid insulation above the roof sheathing. Once insulation is in place, I will install drywall. The firesprinklers have covers for them (similar to photo) with fusible links that will open in extreme temperatures.

Asked By Dan Burgoyne | Apr 29 15
10 Answers

Has anyone had experience with the Unico small duct system?

I was looking at the top finishers for the department of energy's "Race to Zero Student Design Competition" ( http://energy.gov/eere/buildings/2015-results ) and found the winner used the Unico system. http://www.unicosystem.com/the-system/how-it-works/air-handlers/. I recall actually being in a home in Chattanooga once 15+ yrs ago that I believe had one of these systems, but I really know nothing about them. With the problems associated with finding small enough systems for well insulated homes and cost effective systems...does anyone know if I should be looking at this as an alternative?

Asked By Andrew Bennett | Apr 29 15
10 Answers

Recirculating OTR range hoods & washer/dryer ventilation

I'm installing an electric range in a small house, and am considering a microwave with a built-in recirculating over the range hood (with filter). The house is very small (500 s.f.) and pretty tight, and California T-24 code requires continuous exhaust ventilation, which I plan to have in the bathroom (Panasonic WhisperGreen), but I'm afraid if I put an additional exhaust fan in, I'd have to provide ventilation in from outside. How effective are these OTR recirculating hoods?

Asked By Dan Burgoyne | Apr 28 15
Register for a free account and join the conversation


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