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12 Answers

Insulation Baffle in *corner* of hip roof

I am installing my insulation baffles for the attic. I have run into a problem. My roof is a hip style and the corners have a main bridge truss that the smaller guys attach to to form the corner. The first two immediate rafter bays in the corner have very little room. The next two on each side have a little more room as you can see, which I just cut the insulation baffle at an angle to fit in.

In General questions | Asked By Nicholas C | Oct 27 15
2 Answers

Pro and cons of 1-part vs. 2-part foams

I'm in the middle of a new construction and have been using both 2 part foams and 1 part foams to seal around openings. Is there any advantage of one over the other? The only difference I can see is that the two part cures very quickly, sometimes too quickly, but the mix goes out of wack at in the last 15% of the tanks. Is there a substantial difference?

In Energy efficiency and durability | Asked By Geoff Frood | Oct 27 15
1 Answer

Adding rigid foam insulation: What type and how thick?

I've got a 2-story farmhouse with load-bearing double-wythe brick exterior walls with no insulation. 8 years ago I had 6 inches of open-cell Icynene foam sprayed in the attic on the underside of the roof deck, which is sloped on the sides, but flat in the center (see included drawing). I was originally thinking I'd use open-cell spray foam to insulate the walls of the house also, but wasn't sure how I'd go about doing it. I thought I might build an interior stud wall, and then fill it with the open-cell spray foam.

In Energy efficiency and durability | Asked By Darin Weisensel | Oct 28 15
1 Answer

Pole barn — ceiling vapor barrier?

I live in Alaska.. far northern Zone 7 probably zone 8. I have a pole barn that has metal siding and a metal roof on large wooden rafters. Shop/Barn is 45x50x14 and 8/12 pitch with stud walls and lathe is currently in place for the ceiling. The attic area as you can see is quite large due to the size and pitch of the roof
I am thinking about using metal interior panels as the ceiling (basically metal roofing without the UV paint protection) as opposed to sheet rock.


In General questions | Asked By James Williamson | Oct 27 15
3 Answers

GBA page not working

All i get is a blank page, i'm on windows 8.1m firefox 41.0.2

In General questions | Asked By Alan B | Oct 27 15
3 Answers

Installation question for vertical metal siding (reverse standing seam) over Tyvek

house under construction in coastal zone 3 (2-story 2x6 wood framed). Exterior walls are 1/2" plywood
w/tyvek housewrap. Owner wants to install vertical metal siding (reverse standing seam "rustwall") over tyvek house wrap and is concerned about the heat build-up melting the tyvek. I have been asked to advise whether to
1: take the tyvek off and start over with a better detail (I typically detail 1" polyiso w/ a weather resistive barrier over that and then a vented air gap w/battens to hold off the siding
2. come up with another detail to keep the siding off the tyvek.

In Green building techniques | Asked By Peter spellman | Oct 27 15
12 Answers

Design Charrette: General Building Envelope Questions for Mixed-Humid Climate

I'm in need of some focused input on the overall insulation strategy for a home I'm designing, and rather than taking hours upon hours searching through the archives and reading what now seems to be seemingly countless (and often divergent) opinions on these matters, I'm hoping through a quick online charrette a general consensus could be found to help me and my client understand the best route to achieving a fairly high-performance home for a mixed-humid climate (only!) in the Blue Ridge Mountains (meaning we don't get quite as high humidity levels as lower elevations, but can get some fairl

In General questions | Asked By Marc Manley | Oct 26 15
2 Answers

How much time after spray foam should batts be installed in a flash-and batt job?

Due to off-gasing of closed-cell foam, how long should you wait before batting?

How would one check if curing is complete?

If batts are installed to soon, will they then retain the gases?

In General questions | Asked By kevin Mccarthy | Oct 27 15
2 Answers

Roofing - rigid insuation above, plus foam in roof framing bays

I am refering to and creating details based on this on your site http://www.greenbuildingadvisor.com/sites/default/files/Insulated%20cath...
My question relates to the note that calls for breathable insulation on the interior. I want to use non-breathable closed cell foam in the bays so we do not have to vent the roof, which does not have an attic. Project is located in Pismo Beach, CA. Any way we can accomplish this?


In Green building techniques | Asked By Micah Smith | Oct 27 15
9 Answers

Suggestions for non toxic dishwasher and range?

moved into a house with new appliances last november.. the maytag range emits noxious fumes when over 400 degrees...have to open all the windows and exhaust fan on....is there some sort of formaldehyde or high vocs they use for insulation of the range walls, or a finish material...headaches and nausea even after all this time...should we just get an older model used range? did they manufacture those using toxic products as well?

In Green products and materials | Asked By Carole Wiles | Oct 23 15
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