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2 Answers

Passive house and sunshine hours

is there a ballpark rule of thumb that spans different regions for the mean monthly sunshine or possible percent sunshine that is conducive to a favourable result in PHPP?

In PassivHaus | Asked By erik olofsson | Apr 20 14
4 Answers

Rigid foam insulation over Bildrite during remodel/reside?

I have a recurring question / situation that comes up in my east central MN location (6b-7a border). There are many 1970's homes undergoing remodeling and looking to add insulation for improved comfort and energy effciency. Miost common construction is drywall, kraft faced R13, 2x4 walls, 3/4" Bildrite (asphalt fiberboard sheathing).

In Energy efficiency and durability | Asked By Troy Tvedt | Apr 17 14
1 Answer

Ductless Mini Splits & Cassette Units

Are the ductless minis that utilize a cassette unit vs a wall unit, less efficient?
Are there any drawbacks to a cassette unit over a wall mounted unit?
Lastly, can a cassette unit be mounted on a wall or is that not a good idea?

In Mechanicals | Asked By Peter L | Apr 19 14
1 Answer

How best to insulate a traditional slab paired with a wrap-and-strap timber frame?

Hey folks, been reading the site for a while during our planning process and its time to start asking some questions.

In Energy efficiency and durability | Asked By Erik Schmitt | Apr 19 14
2 Answers

Old Home Bathroom Reno

Thanks for any suggesWhat is a good old bathroom exterior wall progression method (1947 home in Edmonton, Alberta) ?

From outside to inside: cedar siding, then 2X6 Douglas Fir planks, 12" studs.

What would be a good insulation choice?

What would be a good baker board choice?

What would be a good drywall choice?

Should a vapor barrier be used?

Will also be installing a bathroom fan- horizontal exhausting through exterior wall due to possible vermiculite/asbestos in attic. What would be the specs for this? It is difficult to find information for this unusual location.

In General questions | Asked By Lisa MArtin | Apr 15 14
7 Answers

Which is the better method for an effective air barrier?

In building a home in zone 4 (western NC), I am interested in determining the better way to go to create an effective air barrier:

Outside in:

Option 1: Hardie, 1 x 4 Furring for 3/4" Rainscreen Gap, 2" Roxul ComfortBoard IS, #30 Felt, 1/2" MgO Sheathing, 2 x 6 Stud Wall with 5 1/2" of Roxul ComfortBatt in the Cavities, 1/2" Mgo Wall Board using the Airtight Drywall Approach

In Green building techniques | Asked By Stacey Owens | Apr 17 14
10 Answers

Does a viable (performance and cost effective), non-foam option exist for under slab insulation?

First, I'd like to thank the many pros and contributors here at GBA. I have been reading and learning for quite some time. Thank you all, first for caring about green building, and second, for being willing to share your time and expertise.

In Green building techniques | Asked By Stacey Owens | Mar 31 14
2 Answers

Vented crawl space

We're building a pretty good green home in Gardnerville, NV, a place that gets 8" rain per year. We get cold in the winter (-10°) and are pretty warm in summer, about 10 days with >100° temps. Radon is an issue in our area. Our new home is being constructed with SIPs, therefore no attic space. We have natural gas at the site, pretty cheap in Northern NV. Our plan is forced air heating via Natural Gas in winter and a few days in summer when we'll use A/C.

In Green building techniques | Asked By Richard Starrett | Apr 18 14
6 Answers

Net-and-blow cellulose vs fiberglass?

We are finishing a space above our garage, about 26 x 26', to make a studio, and are trying to keep costs down and still insulate it well. Is the difference in price between the two types justified in improved insulating quality over time or is the actual insulation pretty comparable? The cellulose people are adamant about their product, and the fiberglass people say the difference is negligible. And then how much more/less green are the two? Thank you!

In Energy efficiency and durability | Asked By Patricia Basha | Apr 17 14
1 Answer

Insulating bottom of radiant floor

I have a radiant floor that was installed under my kitchen floor using the aluminium heat transfer plates. Below the kitchen is a semi finished, semi conditioned basement. I would like to insulate the floor to allow as much of the heat from the pex tubing to translate to the floor (rather than helping heat the basement). Is a radiant barrier (foil) with an airspace beneficial? does the insulation need to be installed airtight? Is fiberglass a good choice in this application? Any insight is appreciated!

In Energy efficiency and durability | Asked By Pete Marthaler - Zone 7 | Apr 18 14
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