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4 Answers
Insulating a Gambrel Roof

My location is Castlegar BC, 3hrs north of Spokane WA.The Insulation Contractor wants to drill holes into the walls and fill with loose fiberglass.I do believe there is a single batt of insulation in the wall cavities so will this interfere with the even distribution of the spray in insulation?

Asked By sarah matheson | May 24 13
5 Answers
Advice for rebuilding in central Oklahoma?

Two degrees of separation from two of the many who lost homes in the recent tornados near Oklahoma City; wanted to tap the collective intelligence to work through how to 'build back better' (or retrofit surviving homes for resilience); both in terms of 'what', and 'how'; espcially, what is locally appropriate / cost effective, specific technical resources, etc., given the unique (and extreme) conditions in OK (tornado, fire, hail, and recently earthquakes...!)

To start the conversation (I will also work on answering my own questions here as I find more information):

Likelyhood of anothe

Asked By David Gregory | May 24 13
24 Answers
Basement insulation for a 1930 house retrofit (wall and slab)

Greetings:

The northern Massachusetts house where I am now living had some very bad energy efficiency characteristics when we moved in last summer. These included:

* a poorly insulated attic with an HVAC system in the cold zone

* an uninsulated basement with 18 inch thick fieldstone walls

Last December we took care of the problem with the attic by installing closed cell spray foam insulation. I got some great advice in this forum -- see http://www.greenbuildingadvisor.com/search/node/1930 . Now the attic is toasty and the house is less drafty.

Asked By rich cowen | Mar 17 11
3 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.

Asked By Bob Brown | May 24 13
3 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?

Asked By Adrienne Raymond | May 22 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?

Asked By Sal Lombardo | May 20 13
1 Answer
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?

Asked By Daniel Stewart | May 24 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.

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?

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?

Asked By erik olofsson | May 22 13
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