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37 Answers

To crawlspace or not to crawlspace?

We are a group of four builders in Quebec breaking ground on a new construction this summer. We’ve been arguing over the niggly details for three years as we try to cobble together the most common sense, super-efficient, affordable house possible. As we seem to be proving, the discussions on how to build can go on forever...

Asked By William | Jan 20 16
3 Answers

Do I need to vent soffits in with an unvented roof assembly?

I have large 4 foot exterior soffits. I am spray foaming the inside of the roof, an unvented attic assembly. Do I still need to vent my exterior soffit overhangs? Do I need to worry about the air trapped in that cavity if I do not?

Asked By dean sandbo | Feb 11 16
6 Answers

Roof clips

Our roof will be 12/12 pitch with 2x6 raifters,would it affect much if we changed to 2x8 to fit a little more insulation,also our roof deck is 7/16 osb taped with a 1.5-2 inch polyiso nailbase on top if that,do you think we need roof clips on the first layer of osb or need to change that to 5/8osb?
Thanks

Asked By Quinton Bryant | Feb 11 16
19 Answers

Mitsubisi Heat Pump- heat and cool

I am building a 1 1/2 story barn/garage 36 X 34 with an open upstair 2nd floor. It will have 2" form in the walls and 3" sprayed form in the ceiling. Cement floor. not too many windows and 2 garage doors.

I don't need it heated like a home but just confortable when I work in the barn. I would like to keep it about 40 degrees in the winter when not in use and will rarely need it cool in the summer. I live in southern CT.

I've been looking at the high efficienty units around 24,000 BTU. I also need to be able to set the temperature low (about 40) when not in use.

Asked By Fred Gabriele | Jan 31 16
15 Answers

Proper crawl space encapsulation and also radon mitigation questions

Hello, I own a 1968 cape cod style home in East Stroudsburg in the Poconos, PA (region 5). It has a full basement with 7' ceilings and concrete floor with probably little to no crushed stone underneath. At some point, there was a ditch cut out along 2 of the walls, with stone and probably a perforated pipe added, and concrete poured back except for a small channel along the block wall. This leads to a sump pit.

Adjacent to one of these 2 walls is a crawl space entrance where an addition was put in.

Asked By Ryan O'Rourke | Jan 26 16
1 Answer

Steel-sided, conventionally framed, closed-cell-foam-insulated home

I have been pondering building a low cost, high efficiency, low maintenance retirement home, and would like some input on my theoretical systems.

The structure would have conventionally framed, 2x6 walls, with no sheathing. In it's place, would be diagonally place structural supports(2" x 2") spaced at 24". In that 24" space would be 2" foam. The wall would than be strapped horizontally(2" x 2"), and spaced at 24" with foam in that space as well. The steel siding would then be installed, and attached to the horizontal strapping, and through to framing.

Asked By Maine Builder | Feb 11 16
16 Answers

Are holes in exterior plywood sheathing necessary?

We are building a new home on the west coast of BC. Our framer has placed large diameter holes in the exterior plywood sheathing saying this is necessary to meet code and allow the exterior to breathe. Our concern is that when other protective layers placed over the sheathing break down over time (plastic and tape and glue only last so long) we have a welcome entry point for water, rodents, carpenter ants ect. How does this practice fit into an 'airtight' home??
We are not builders but can't find anywhere noted that these holes are necessary. Thoughts, advice or comments appreciated.

Asked By Frances Bucinel | Feb 10 16
2 Answers

Rigid foam on the roof

We are remodeling the exterior of our 115 year old farm house this year and felt it would be a great time to tighten the envelope and add rigid foam to the exterior. However, our contractor has some concerns about the extra weight of five inches of foam over the roof. Is this a valid concern? It's an old house. The frame of the roof consists of actual 2x4s placed 24 inches apart. We nailed 2x12s to the 2x4s eight years ago to provide a cavity to put blown in cellulose.

Thanks for the advice, Ryan

Asked By Ryan Knight | Feb 11 16
3 Answers

Insulating walls and ceiling for a barn workshop

Hi Folks,

I am in the process of building out my 1350 sq ft barn for use as a sculpture studio (i do mostly wood and metal fab). I use the space year round, and before insulation I can barely keep it in the low 40s with a 35k BTU pellet stove running 24/7.

The barn is sided with 1x12" eastern pine board and batten (all dims are actual not nominal) The roof and walls are 2x6 rough hemlock or eastern pine. Between the b&b siding and the studs is a very cracked/UV damaged poly barrier.

Asked By Benjamin Jones | Feb 11 16
9 Answers

If the IRC specs a 3.5" nail for framing, why do so many use just a 3.25" nail

For over 20 years I've been using a collated 16d (3.5") nail in my nailgun for framing walls. I'm in the market for a nail gun upgrade (changing brands) and found that many best nail guns only go to 3.25".

The IRC states that (2) 16d nails are needed to nail studs to the plates, why then a 3.25" nail and why do so many nail gun manufacturers not make a gun that shoots up to 3.5"

Can any of you expand on this?

Asked By Brad Hardie | Feb 11 16
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