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4 Answers

So we haven't hired the builder of our future house yet, and are trying to figure out how to ensure that air sealing is a priority for the builder as well as for us. Certainly, we will specify what we can, and will choose someone with a good reputation and an apparent commitment to quality work. Still, the best plans depend on execution, and not everyone thinks of 4 ACH 50 as a bad score. It seems that 2 ACH 50 should be a good result and reasonably achievable, but how do I get a builder to really try to achieve it?

In Green building techniques | Asked By Ian Brown | Oct 19 11
2 Answers

Hi All,
All the local builders I have asked use highly toxic glue to hold the window sills down. Does anyone recommend a green, more sustainable material?
William in Vermont

In Green products and materials | Asked By Styles Brook | Oct 19 11
5 Answers

In lieu of Martin's suggestion; can a propane gas furnace in an attached garage be brought into the house thermal envelope by just framing in around it with insulated walls and access door?
Furnace and hot water tank are vented together.
Preexisting bedroom is on other side of garage wall.
What code violations to avoid?

In Energy efficiency and durability | Asked By James Cavallaro | Oct 17 11
7 Answers

My wife and I will be building our house next year. I’m in the research and planning stage and first order of business is to determine our insulation strategy. We’ll be building in eastern Ontario (near Ottawa) which sees average winter temps of around -13C (7F). I’ve recently come across the dew point calculation method posted last year by Martin. I was thinking of going the route of 2” XPS foam board with rock-wool cavity insulation on a 2X6 wall. Here are the calculations (assuming 70F and 35% humidity, therefore giving us a dew point near 40F):

Temp delta = 70F - 7F = 63F

In Energy efficiency and durability | Asked By Mike Goulet | Oct 14 11
5 Answers

In the next couple of years we are going to build a house in a town near Montgomery, Alabama. Since I have been gone from that area for over thirty years things have changed. We live in the north now and we have hot water baseboard heat. We love it. But the south, I think they use heat pumps. Which would be the best. Air or geo.

In Energy efficiency and durability | Asked By William Wingett | Oct 18 11
3 Answers

We recently experienced light 'flooding' of my unfinished basement that I was in the middle of framing. In order to get items away from potential water damage, I moved 10+ rolls of unfaced batt insulation into my crawlspace (which is 3 feet above the height of the floor of my unfinished basement). Well to get the rolls in the crawlspace, I had to open the rolls and layout it out directly on the dry vapor barrier. I proceeded to take care of the water on the unfinished basement and left the insulation on the floor of the crawlspace.

In Energy efficiency and durability | Asked By Ben Johnson | Oct 9 11
7 Answers

I have a row house in Philadelphia that suffers from constant dampness. I have dehumidifiers running constantly, but really need to address the "antique" foundation. Half of the basement is ancient brick (c. 1890) and half very thin concrete (1-2"). The problem is the there is no way to have concrete poured into the space as it is:
a. set back off the street and surrounded by an iron fence
b. down some extremely steep stairs
c. only accessible from the exterior by two small windows
I don't think I could even get a mixer in the house and down those stairs.

In General questions | Asked By Hayley Gresens | Oct 15 11
5 Answers

Hi all,


I live in an area where temperature's varies from -40 to +38 deg Celsius. I have a home built in the 1940s and I have a question about increasing the insulation in exterior walls. Note, my foundation footprint is a rectangle.

At construction, loose coconut fibre was placed between the studs, and no vapour barrier was installed. I've done some research and have found that about 4" of loose cocounut fibre equates to about an R3.

In General questions | Asked By Robin Moll | Oct 13 11
6 Answers

I recently entered a home purchase in SE Michigan and now find myself with a cathedral roof problem. There are cathedral ceilings throughout the upper level of the 2 story home; built in 1979. The main floor living room area is open all the way cathedral roof, and also to the basement with an open stairwell (serious stack effect going on). There is evidence of condensation on the walls coming from the cathedral wood panel ceiling which is attached to the underside of the rafters.

In Energy efficiency and durability | Asked By Brian S | Oct 13 11
6 Answers

I'm planning on residing my 1970's house soon.
- I currently have T-1-11 nailed on the studs (both sheathing and siding) with 15# felt under it.
- I will do lap siding & shingles over battens to create a rain screen over the T-1-11.
- Location is western Oregon (temperate & wet)

In Energy efficiency and durability | Asked By Thomas Farwell | Sep 26 11
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