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2 Answers

Is it worth the effort? Attic insulation detailing.

My home is a 1950, 2 floor, brick colonial in the Detroit area (5A). This place was built with no wall insulation. There is still no wall insulation.

In Energy efficiency and durability | Asked By GARY ZIRULNIK | Mar 26 12
1 Answer

Thermal Bridging of I-Joists

Building living space over a garage (zone 5-Colorado).
Floor will be 12" I-Joists (3/8 web) with blown cellulose (R-42).
Roof will be 12" I-Joists with blown Cellulose (R-42) plus 2' foam (R14).

Given that the delta T (garage to Living) is only about 40 degrees, do I need to worry about thermal bridging with R-42?

Second question: Have seen a couple double wall projects where the inspectors required 3/4 plywood fire stop every ten feet. Wouldn't this diminish the advantage of double wall?

In Energy efficiency and durability | Asked By Richard Patterman | Mar 26 12
2 Answers

Mass. glazing requirements for school buildings impede energy efficiency

It appears that Massachusetts now requires low solar heat gain (below 0.4) for windows in school buildings constructed with state aid:

http://www.massschoolbuildings.org/sites/default/files/edit-contentfile/...

The SGHC must be no higher than 0.4, according to page 186 of this document.

In Building Code Questions | Asked By rich cowen | Mar 26 12
3 Answers

I have three energy reduction measures.

Electricity is the only energy power.
One measure saves 25% . The second saves 7.5% and the last one saves 10%. What is the total saving?

In Energy efficiency and durability | Asked By Hanan Waizman | Mar 25 12
0 Answers

A Treehugger blog comments on a GBA story

Lloyd Alter of Treehugger.com has posted a blog commenting on a GBA news story about the Passivhaus petition: A Plague On Both Their Passive Houses.

In PassivHaus | Asked By Martin Holladay | Mar 26 12
2 Answers

Putting insulation in a wall that has none

Just moved into a new (to me) home in Southern California. A single family house, built 1965. I'm relatively new to DIY home improvements but fairly ambitious. I decided to work on upgrading a bathroom and started by tearing down the tub/shower wall in an upstairs bathroom. I got everything out to the bare studs and noticed there is no insulation. I see a thin black paper-like material that is breaking apart and behind that is (what I think) is concrete, then it must be the exterior stucco or something. So, before I build the wall back up, can/should I put insulation in this wall?

In Energy efficiency and durability | Asked By Newman Yen | Mar 25 12
2 Answers

Looking for storm door detail

I have added 2 layers of 1 inch foam and then 1x4 vert, furring . but having trouble finding out how to or were to put the storm door . it appears i have to put it on the ext. foam but that leaves a big gap between the entry door. just looking for some plan details . this sight shows window and door details but dont show any door detail. any help would be great. thank you

In General questions | Asked By richard friend | Mar 24 12
2 Answers

Blown-in floor joists... cellulose vs FG... your opinion?

I'm about to have an insulator install blown-in insulation in a 2x8 framed floor. This is Zone 4 marine, over a crawl space that is very well vented. He is willing to do either cellulose or fiberglass. What if any are the considerations?

In General questions | Asked By David Meiland | Mar 25 12
5 Answers

Metal Ag roof over doubled up foam and ice and water shield

I would like people's opinion as to whether an ag style metal roof (exposed fasteners w/ neoprene washers) would be sufficiently leak proof if installed on strapping over two layers of foam and ice and water shield as detailed on the site here.

In Energy efficiency and durability | Asked By Joel Cahalan | Mar 23 12
2 Answers

Does anyone know about using crushed shells (clam or oyster) for driveways in Washington State?

We are near the shoreline and are required to use a pervious surface material.

In Green products and materials | Asked By Mona Lydon-Rochelle | Mar 24 12
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