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0 Answers

What kinds of waterproof membranes can I use over the top of radiant in floor heat?

I'm currently working on a remodel of small dorm building at The Evergreen State College in Olympia WA. We're planning on installing STEP warmfloor radiant heat, but we have some concerns about installing it in the bathrooms.

Is there a kind of membrane we can install over the heating element, under either laminate or tile that will protect the element from water damage but can also withstand the heat?

In Green products and materials | Asked By Evergreen State College | Dec 5 12
15 Answers

Zone 5 - Different wall options

Building in Nebraska (Zone 5). Builder proposed 2x6, 1/2" spray, then fiberglass batts.

I understand 1/2" sprayfoam would raise condensation issues. In meeting with the builder soon, I will propose three alternatives:

-2x6 wall but 2" sprayfoam, then fiberglass batts/blown fiberglass/cellulose, depending on price and availability.

-2x6 wall and 2" rigid foamboard on exterior, then fiberglass batts/blown fiberglass/cellulose (my builder has not done this before and may not be comfortable with this)

In Green building techniques | Asked By Cameron Guenzel | Dec 4 12
6 Answers

My insurance company, Vermont Mutual, refuses to issue a policy for a home with a pellet stove.

They said they don't care if it meets code, or even if it is functional. If there's a pellet stove, there is no insurance policy. How can I deal with this?

In General questions | Asked By Michael Mertinooke | Dec 4 12
2 Answers

How do I prevent overheating in a 2nd floor (cost effectively)?

I am trying to help someone problem solve and over heated 2nd story here in Portland, OR. This person has central A/C, but doesn't like using it and it doesn't effectively cool the 2nd floor as well. The house has vaulted ceilings, which makes adding a 2nd floor return in the ceiling cost prohibitive.

The client is open to a wall mounted fan. Given that we live in a heating climate, does anyone know of an insulated wall mounted fan that would work for this application (2x6 walls).

Any other bright ideas?

In Green building techniques | Asked By Tyler Dotten | Dec 4 12
2 Answers

Wall energy performance upgrade strategies?

I'm planning to remodel my home and seriously upgrade its energy performance.

The house is a single-story, 2000 sf, 1950s brick-veneer ranch in Dallas, TX (zone 3a?). It is very poorly insulated/sealed and windows are single-pane aluminum sieves. The foundation is pier and beam; the crawlspace is vented.

In Green building techniques | Asked By Andrew Thompson | Dec 3 12
8 Answers

How can I limit the thermal bridging, and eliminate the potential for interior condensation, at a cantilevered steel deck?

I'm an architect working on the remodel of a single-family dwelling in San Francisco (Climate Zone 3C). My client wants to maximize the city view, so steel will be used for a rigid steel frame at the view side of the building, for the structural frame of a cantilevered deck, and for posts and beams at a number of exterior walls.

In Energy efficiency and durability | Asked By Steven Whitney | Dec 3 12
1 Answer

How to insulate roof?


I am renovating this old porch addition and want to insulate it properly. There must have been some moisture issues before because some of the OSB has what looks to be mold or something moisture related. Luckily it doesn't seem to smell and it still feels firm. I'm speaking with a spray foam installer today but I have the feeling that cost for the size of the ceiling (145sq.ft.) is going to be rather... expensive.

In Energy efficiency and durability | Asked By benjammin p | Dec 4 12
2 Answers

Furring strips required over 1" rigid foam insulation?

Planning the renovation of a 110 year-old cottage in Indianapolis. Looking to put 1" of rigid foam on the outside before re-siding with fiber cement lapboards, and 3.5" of wet spray cellulose inside. We do have wood sheathing, horizontally hung 1x boards, on the exterior of the wall studs.

Is the furring strip over the foam advisable because it will 1) allow air circulation behind the siding or 2) provide structural support when hanging siding? Or both?

Or, with the relatively narrow foam, is it not required?


In Green building techniques | Asked By William Wagnon | Dec 4 12
4 Answers

Worried about air sealing fireplace attic vent cavity

I'm an insulation contractor and I also try to close up the "big" air sealing holes before we blow in additional loosefill insulation. I want to close off the enormous cavity the builder left for the fireplace vent stack. My concern is how does a fireplace draw fresh air from combustion? Do I need to leave this cavity open to prevent back drafting?
Thank you for your responses.



In Energy efficiency and durability | Asked By Randy Ransom | Dec 3 12
9 Answers

Help me design a small building heating/cooling solution

Hi Folks,
My wife and I have just bought piece of property outside of the Boston, MA area (Zone 5a), and we will be building a home there next year (hopefully...just going through the close process). Currently on the property is an existing structure that I am planning on rehabbing, to use as a detached home office and workshop.

In Mechanicals | Asked By Jonathan Petersen | Dec 3 12
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