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8 Answers

How Risky is this Assembly?

On a scale of 1 to 10 how risky is the following assembly? 1 indicating that the assembly is safe, and will remain dry and mold free for several years and 10 indicating that the sheathing will be soaking wet and we'll have mold in our walls in no time. We're in zone 6A, 30-40" of avg rainfall.

In Green building techniques | Asked By Kelly Walters | May 26 13
1 Answer

Should I vent my roof system or not?

A well known SIPS panel manufacturer that I am currently dealing with has said they will not warranty their structural panel without a ventilation layer if asphalt shingles are installed directly onto the structural panel. I have recently designed and am currently building a house incorporating what I have come to believe are realistic energy conscious features ie. ICF foundation, insulated basement slab, air source heat pumps... I specified and installed the Adventech zip roof panel w/ tape with the intention of building a hot roof consisting of closed cell insulation with no venting.

In Energy efficiency and durability | Asked By Mark Nicotera | May 24 13
1 Answer

Whats the best method to waterproof a new foundation?

So far the footing is in. It sits on top of a foot of gravel that was compacted. There's perforated pipe along the inside of footing that connects to a sump pump. The back fill will be sandy soil. I plan on using the asphalt for damp proofing and then platon membrane on top of that with 2" of xps or 3" of eps insulation on top of that. Does this sound decent? If I put the insulation to the top of the foundation what can I use to cover it so it won't look ugly?

In Energy efficiency and durability | Asked By Jason carreiro | May 24 13
2 Answers

Compressible gasket under car decking

I'm working on a house where the roof will be exposed glulam beams with tongue and groove car decking as the finished surface. The car decking will extend continuously beyond the wall and become the soffit for the overhang. I'm concerned about air-sealing between the car decking and the top plate.
I was thinking that some kind of compressible gasket or foam would be able to compress into the chamfered "v" shaped sections of the car decking.

Is there a specific product that would work for this?

In Green products and materials | Asked By Daniel Stewart | May 24 13
4 Answers

Insulating an interior chimney

I have a 200-year-old 1 1/2-story Cape in mid-Vermont. Over the years we have added insulation most everywhere and last year had significant attic and basement sill air sealing done. This past winter we still saw ice damming on the main part of the house. We heat with wood and have a woodstove connected to one of the flues in the central chimney.

The chimney gives off significant heat into the unheated attic space. Is this a problem? Can I wrap it with mineral wool? Will that help? Or should I quit using that flu in winter?

In Energy efficiency and durability | Asked By Adrienne Raymond | May 22 13
5 Answers

Draw air from vented attic?

I am looking at a zero-clearance fireplace which is designed to draw outside air for combustion and for air to be heated from the outside. It is suggested that this air be drawn from a vented attic. Is this a good idea?

It seems like it would be possible for this system to pull air into the attic from the house through leaks (supposed to be no leaks, but ..... you know). Of course there could be adequate vents to supply the 300+ CFM for the blowers, but there might not be enough, or this system might pull air in through the ridge vent which might not be a good thing.

In Energy efficiency and durability | Asked By Bob Brown | May 24 13
7 Answers

Insulating or NOT insulating the basement slab

I previously had asked about the potential of constructing a rudimentary geothermal basement by purposefully NOT insulating the masonry walls of a basement. Martin pointed out that the ground temps in NY/NJ/CT in winter at the surface are freezing and not until something like 48 inches are they above freezing, say around 40 to 45 degrees? Thus making it clear the walls should be insulated. But what about the the floor slab? Assuming a depth of say 9 feet at the slab's underside, would this not be a constant 55 degrees or so? Thus be warming in winter and cooling in summer?

In Energy efficiency and durability | Asked By Sal Lombardo | May 20 13
6 Answers

Will my insulation plan work?

I am in the course of remodeling an 1860s balloon-framed farmhouse in NE Pennsylvania. I am currently reinsulating the attic. It originally had only R-19 fiberglass insulation in it which had discolored due to numerous air penetrations.

In Energy efficiency and durability | Asked By Ben Hardy | May 23 13
5 Answers

Blower door questions

We are about to perform a blower door test on our small 650 sq. ft. new construction house. I have four quick questions:

1. We used T&G OSB and Siga tape for our air barrier, and i think we did an extremely thorough job detailing it. the house is not quite complete, however. for example, the clothes dryer is not installed, some of the joints in the hrv ducting in the crawlspace have not been sealed, the drywalled window returns have not been latexed to the window frames, etc... will these items have a significant effect on the test results?

In General questions | Asked By erik olofsson | May 23 13
23 Answers

Cold sheathing question

Martin, I read your article on cold sheathing. I'm still not clear on one point: how do you know if the sheathing is wet due to the sheathing being cold and taking on moisture or the sheathing being wet due to vapour making its way from the interior of the house?

In General questions | Asked By erik olofsson | May 22 13
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