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1 Answer

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.

Asked By TERRY KELLEY | Jul 23 14
Answers

I am looking to use a detail similar to 4-05055 - metal roof/unvented/cathedral/exterior 4.5" rigid insulation. I have a few questions on the assembly:
1- are the layers of rigid insulation adhered together?
2- what type of fasteners are being used to go thru the first layer of sheathing, thru 4.5" insulation, 2nd layer of sheathing and into rafters? spacing? (I am located in NY - 90 mph ground wind)
3- do you know a relative comparison between this detail and using a SIP panel - cost? installation? structural?

Thank you!

Asked By Linda Zwart | Jul 23 14
Answers

Given all the complex issues covered on this site, this question might seem rather pedestrian....

I am not going to change out the doors on my house, but I would like to get them more airtight. In particular, I have two sliding patio glass doors, and my front door is a wood double door that has one door latched into the other (double swing in without a jamb piece between the individual doors).

Asked By Steve Young | Jul 23 14
1 Answer

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.

Asked By JOANN CORTINA | Jul 22 14
1 Answer

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.

Asked By Janet Blayone | Jul 22 14
1 Answer

Which type of spray foam is recommended, open or closed-cell?

I'm about to remove my blown-in insulation out of the attic, and I was trying to figure out which product is recommended -- the open or the closed-cell?

Asked By TERRY KELLEY | Jul 22 14
3 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
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
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