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3 Answers

For zone 6, when building a new construction wall assembly, why wouldn't this method work well- starting from the exterior side- OSB sheathing, Roxul R-23 cavity insulation, 1-2" foil-faced polyiso rigid board placed continuously over inside of wall, joints taped appropriately, furring strip, drywall. It seems that this would pose the least risk-as the continuous foil-faced polyiso will stop to a great extent vapor transmission. I realize that no assembly is completely vapor leak proof, but the OSB can dry to the outside if need be.

Asked By Peter Nadler | Jul 22 14
2 Answers

Hello Again!

I am trying to decide on the best weather barrier to use on my house, and would like to hear some opinions on liquid applied WRBs. I am looking at Henry Air-Bloc, for example. I am inclined to think that a liquid applied weather barrier would be more effective than a housewrap like Tyvek, but can't seem to find confirmation one way or the other.

I am hoping to use this external layer as my primary air barrier, so it is critical that it be as effective as possible.

Asked By Stephen Youngquist | Jul 22 14
3 Answers

I'm evaluating blown cellulose vs. blown fiberglass (Knauf Ecofill). The Oak Ridge study is often quoted regarding the drop in R-value of blown fiberglass when the temperature differential is high. However the tested fiberglass density (.4 - 5 lb/ft^3) is much lower than the newer fiberglass.

Asked By Neil Weinstock | Jul 21 14
3 Answers

I'm in the planning stages of a remodel and need to make a decision about cooling.

Asked By Eric West | Jul 21 14
1 Answer

Starting a new build (1 1/2 basement walkout), all 2x6 exterior walls w/ brick veneer in GA, CZ 3. Above grade, would like to do spray foam in 2x6 walls, 1/2" or 1" of rigid foam board on the exterior, and a 1" air gap. Will this require a housewrap or can I do without the rigid foam and go with a housewrap? Also, any recommendations about insulation strategies for the finished basement. Thanks!

Asked By David Myles | Jul 22 14
Answers

Has anyone recently imported high performance windows to Canada? I'm currently looking at both Canadian and European windows for a house in southern Ontario and would be very interested to hear about any experiences, good or bad, that the GBA community has had.

On a side note, the Canadian market for high performance building products seems so small that finding local dealers for many products seems tough. Other than ordering from Small Planet Workshop or Four Seven Five, are there any good sources out there?

Asked By Graham Fisher | Jul 22 14
2 Answers

We had our basement encapsulated in the fall last year and made it through winter no issues. They used a thick mil high quality (apparently) vapor barrier and then sprayed /fogged with mold preventative. I don't think there is any more mold - smell is not musty really and I don't get a mold allergy reaction.

Asked By jeff weikert | Jul 22 14
1 Answer

We are in the planning phase of a passive house near Louisville, Ky. The site is a South facing hill with a great view of fields, trees and a creek. We plan on a walkout basement under a 2300 square foot home. I am concerned about moisture through the wall of the basement. Some precast concrete wall providers guarantee water tight walls with insulation on the inside. If they are used what precautions should be taken relative to the floors and vapor pressure to the inside?

Asked By Paul Nicholls | Jul 22 14
8 Answers

Spa covers are very expensive, and very short lived, because they are made of vinyl that tears and expanded polystyrene that absorbs water. Does anyone have any with experience or thoughts on building a spa cover? I was thinking marine plywood and EPS.

Asked By william goodwin | Jul 21 14
11 Answers

I have a simple question about EPS that I'm sure one of you can answer for me. Outside of buildings I encounter EPS in two places where it seems to act in very different ways. I see foam anchor buoys and fish floats off our coast and washed up on the beach that seem to maintain their buoyancy and lightness or years. But those of you with hot tubs will have noticed that the foam inserts gain weight over time and within a couple of years the initially light cover can easily triple its weight.

Asked By Malcolm Taylor | Jul 10 14
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