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2 Answers

My house was built in the 50's, and as is typical for homes in this area, has 1/4 drywall with a real plaster job over it. My question is is this a better/worse/same air/ vapor barrier than standard drywall, taped at seams etc. I'm asking because I'm a little concerned about trapping moisture in the wall now that I've added 5 1/4" or EPS to the exterior. Thanks.

In Green building techniques | Asked By Aaron Vander Meulen | Jan 20 12
3 Answers

Deep energy retrofit combined with extensive remodel of early 60's modern architecture home overlooking Puget Sound. Using cameras we found drain pipes under the basement slab were compromised. We took this opportunity to remove the slab in these areas as well as over areas where two bathrooms are being built, one existing and one new for the master bath, to accommodate hydronic radiant heat. The idea is to install hydronic radiant slabs in these two areas but we want to isolate them from the surrounding slab as well as from underneath.

In General questions | Asked By Greg Lindstrom | Jan 19 12
2 Answers

I’m building a new house in Knoxville, TN (zone 4). This is a wet climate and often dark—enough to require artificial lighting during the daytime in our current house. My wife & I are willing to sacrifice some U value for brighter daylighting, because the resulting personal productivity warrants it (we both feel more innervated on dark days). One of the greatest pleasures in life is to see sunlight streaming in through windows, the way interiors are always photographed in those upscale magazines!

In GBA Pro help | Asked By David McNeely | Jan 20 12
8 Answers

Hi, I wanted to learn more about passive solar heating. I kinda know the basics from reading online, but are there any books on the subject that you all would recommend?

In General questions | Asked By Jay Sheth | Jan 17 12
5 Answers

Cold Climate Housing Research Center, zone 8, just published this, and it may be of use to anyone retrofitting exterior insulation. http://cchrc.org/safe-effective-exterior-insulation-retrofits

In Energy efficiency and durability | Asked By John Klingel | Jan 19 12
6 Answers

We built a log/timber (Lindal Justus) home in 2000 and insulated our 12" roof rafters (I beam) with 6"+- of icynene per thier recommendation. We are now realizing that even though we passed all our inspections and no signs of ice damming this is not enough insulation. The footprint of the home is 1000 sq ft and our rooflines are simple. We have a 12/12 over about half and a 4/12 on the rest. The ceilings are all cathedral with 12" I beam with metal cross braces about half way and finished with 1/2" plywood and shingles on top and 1/2" drywall in the living area.

In General questions | Asked By Scott Doherty | Jan 15 12
5 Answers

Hi and thank you for looking at my question.

I have a newer built house (1993) that is built on a dirt crawlspace with no current insulation either on the concrete walls or in the first floor joists. due to the high water level in the soil and the awkwardness of excavating the current dirt, I am stuck with what approach to take in light of cost and longterm efficiency.

In General questions | Asked By Anthony Hopkins | Jul 24 11
13 Answers

We are looking to build a new home this spring in Southern Wisconsin (zone 6b). While the house plan is being finalized we have been debating the value of building with the local standard 2 X 6 frame house vs. AAC concrete (12 inch Aercon AC4). Majority of homes built in the area are of a simple 2 X 6 frame with no AAC homes that I can find in the area. While it does appear good quality insulation can allow for the 2 X 6 frame to meet an R40 rating we wonder if the AAC will actually provide more benefits.

In Energy efficiency and durability | Asked By Joe Cooper | Jan 14 12
7 Answers

A while back I asked for opinions on my proposed insulation plan for a home I'm getting ready to build in PA - zone 6. The original plan was as follows:

(from inside to outside)
5/8 drywall
2x6 studs 24OC
cellulose sprayed in stud bay (R19)
OSB sheathing
two layers of 1in poly iso foamboard (staggered & taped) (R12)
3/4 strapping
fiber cement siding
approx r value R31

I'm now considering the following

From inside to outside
5/8 drywall
2x6 studs 24OC
3.5" Roxul batts (R15)
2 " closed cell spray (R12)
Zip wall R6 sheathing (joints taped) (R6)

In Energy efficiency and durability | Asked By Jim Orasky | Jan 18 12
1 Answer

I'm installing radiat tubing in the floor joist cavites of my first and second floor addition.

I've been advised that I need to use aluminum transfer plates with the tubing for maximum support and heating efficiency. I've also had people tell me I only need to attach the tubing to the underside of the subfloor by whatever method, then insulate the top two or three inches of the cavity to insure that the warm air there moves up through the floor, and does not fill the cavity and the ceiling of the room below, wasting heat.

In Energy efficiency and durability | Asked By Todd Audsley | Jan 18 12
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