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3 Answers

Is there a place to compare exterior doors for energy efficiency and excellent seals? We are having trouble finding suitable doors for a very well insulated SIP house. The ones we got on a previous job are not adequate.

In Energy efficiency and durability | Asked By Anna Johnson | Jul 20 11
5 Answers

Hi, I want to seal and insulate my ceiling this summer. Old house with lathe and plaster, 2x4 joists, ventilated attic, and 3-4 inches of what looks like mineral wool insulation. Plan was to remove old insulation, seal any holes and cracks, and seal over interior wall partitions. Then add as much blown cellulose as possible though not sure yet if 2x4 joists will limit how much cellulose I can add weight wise.

In below JLC forum thread it was stated that you can't use lathe and plaster as an air barrier.

In General questions | Asked By David Argilla | Jul 20 11
0 Answers

I recently bought a 200 year old timber-frame cape in Western Mass. Right now there is no insulation in the roof. I know the recommended fix is to put rigid foam on top and re-roof, but as the story seems to go the previous owner replaced the roof last year. I know. It is a shame or even a crime they didn't address the problem then. But they were 90+ and had lived in the house for 50 years without insulation so why do it now.

In Energy efficiency and durability | Asked By Jamie Malcolm-Brown | Jul 20 11
6 Answers

I'm replacing some drywall in the corner of my basement - just one sheet on each wall. The block wall on one side (Northeast) is all below grade. The wall on the other side (Northwest) is half below grade. The bottom plate/block connection is not well sealed, so I was going to do that. The builder had a put a piece of poly up over the studs and fiberglass batts on the above-grade portion. the outer sheathing is right behind them. Should I replace this piece of poly or should I leave the fiberglass and studs exposed to increase drying to the inside?

In General questions | Asked By Michael Schonlau | Jul 17 11
5 Answers

update to Paul Ehrlich's 1968 'The Population Bomb' - http://www.pbs.org/wnet/need-to-know/environment/video-standing-room-onl...

In General questions | Asked By j chesnut | Jul 16 11
2 Answers

I have a wall between my basement laundry room and the garage. This is a frame wall with drywall on both sides and fiberglass batts in between. I've noticed some crust white material near the bottom of the interior wall (see photo). Any ideas what might be causing this? There is no moisture damage apparent.

In General questions | Asked By Michael Schonlau | Jul 19 11
16 Answers

Hi again, GBA Forum:

Two and a half years ago, I had the roof ripped off my house and a second story put on. I paid for the envelope including door/window installs, the plumbing, and additional ductwork runs, and did the electrical, insulating of the second floor, and finish work myself.

In General questions | Asked By Minneapolis Disaster | Mar 24 11
2 Answers

I am in the midst of a re-roof that was spawned by water damage. We're taking off concrete shingles and putting on a metal roof (futureroof.com). I am looking for the best insulation that creates a vapor/moisture barrier. I was about to use closed-cell foam.

One cathedral ceiling has 2x4 roof joists that will be shimmed to 4 and a quarter inches. In some places on this roof the original skip sheathing is in place which could be left in place (at least most of it) while removing the batt insulation. This is a nonvented space.

In Green products and materials | Asked By Judith Bell | Jul 17 11
1 Answer

Hello there - I am working on retrofitting a brownstone in Brooklyn NY to near Passive House standards. Considering using Air Krete - I would love to hear some feedback; at first it looks like a good product save to install and enviro friendly; also they state a high R value !
any comments are appreciated.

In Green products and materials | Asked By Dominik Eckenstein | Jul 18 11
14 Answers

I'm wondering what techniques others have come up with to attach porch deck and roof ledgers to exteriors walls with 3" to 4" of rigid exterior foam. I suspect this is a question that begs for an engineer's stamp but I would appreciate an overview of methods others have used to both attach a porch roof, for example, without compromising the thermal break provided by the 3" to 4" of foam. Perhaps one can through-bolt the ledger through the foam directly to the interior stud wall.

In Green building techniques | Asked By Ray Sebold | Jul 15 11
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