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2 Answers

Open-cell vs. closed-cell

Thanks Mr. Holladay for responding to my question however I don't think I was clear with my question. I wanted to remove the floor installation it my atic and replace it with foam installation between the rafters. I've heard many different things about open & close cell that I didn't know what was true or false. What is recommended for the atic ceiling, open or closed cell. What is R value and what number should I try to accomplish with the R value.

In Energy efficiency and durability | Asked By TERRY KELLEY | Jul 23 14
4 Answers

Importing windows to Canada

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?

In General questions | Asked By Graham Fisher | Jul 22 14
1 Answer

How do I figure the size of an air conditioner and a gas furnace for a mobile home?

I am having a new outside air conditioner and a new 2 stage gas furnace put in. My mobile home is from about 1977. It has 1440 sq. ft., floor (out flow vents) & ceiling in flow vents. The present duct work is inaccessible. There is an old 4 ton elec. A/C unit and an old - maybe 100,00 BTU gas furnace. Neither one is efficient. My place is probably not very air tight Don't know about the insulation. I think I live in zone 3C (about 2+ hours N.

In General questions | Asked By JOANN CORTINA | Jul 22 14
1 Answer

I have a roofing / deep energy retrofit question

I have a roofing / deep energy retrofit question. I'm just beginning a deep energy retrofit as a retirement home on a permaculture garden-farm project in northern Alberta, Canada (ASHRAE Zone 8). Tomorrow we are moving a 42’x28’ bungalow 200 km.

As it needs a new roof (old shingles are stripped to sheathing and house tarped at old site), the current plan is to chainsaw the eaves, then apply air/vapour barrier, insulation (either Roxul ComfortBoard or EPS) to exterior walls, preserving as much interior space as possible.

In Energy efficiency and durability | Asked By Janet Blayone | Jul 22 14
3 Answers

Using rigid insulation correctly

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.

In Energy efficiency and durability | Asked By Peter Nadler | Jul 22 14
2 Answers

Liquid Applied vs. Sheet WRB

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.

In Green products and materials | Asked By Stephen Youngquist | Jul 22 14
3 Answers

Evaporative Cooler vs Mini-split

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

In Energy efficiency and durability | Asked By Eric West | Jul 21 14
1 Answer

Spray foam info

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!

In General questions | Asked By David Myles | Jul 22 14
8 Answers

Spa cover

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.

In General questions | Asked By william goodwin | Jul 21 14
11 Answers

EPS characteristics

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.

In General questions | Asked By Malcolm Taylor | Jul 10 14
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