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3 Answers

What would be the best insulation choice for a chemically sensitive family?

What would be the best insulation choice for a chemically sensitive family whose primary concern is indoor air quality for the cathedral ceiling areas that have no attic space?

The home is at 6,000 ft elevation at LakeTahoe, Nevada.

In GBA Pro help | Asked By Neil Adams | Nov 14 12
14 Answers

Bad Appraisal on a New Green Home

We recently received a very poor appraisal on a new home we are trying to build for one of our customers. They/we are shooting for Gold/Emerald certification under the NGBS. Closed crawl, conditioned attic, upgraded insulation, tight envelope, extremely high performace HVAC, solar water heater, passive solar design, etc. Point is, we are not just doing a few small things and calling it green, trying to go the extra mile, shooting for a HERS below 50.

In Green products and materials | Asked By Danny Kelly | Aug 9 10
4 Answers

What is preferred, rainscreen or rigid foam insulation?

If I have only about 1 1/2 inches to work with, which is preferred; rainscreen and no exterior rigid foam insulation or exterior rigid foam insulation and no rainscreen? This wall could be sheathed with:

1/2 inch plywood, 1/2 inch rain screen and then 5/16 inch Hardie panel.

Or, it could be finished with:

1/2 inch plywood, 3/4 inch foam board, and 5/16 inch Hardie panel.

I know that exterior foam insulation AND a rainscreen is the best option, but I am restricted by door trim and an electrical mast that I do not want to move.

In Green building techniques | Asked By Robert Sanders Jr | Oct 23 12
5 Answers

Rainscreen wall with insect screen

I've got a small project where a mid-90's wood-frame wall in the mid-Hudson Valley of NY needs a rainscreen retrofit (paint's peeling off in large pieces, fairly certain there's a bit of moisture getting behind the cedar clapboard and then being cooked in the sun).

In Green building techniques | Asked By Cramer Silkworth, PE | May 15 12
24 Answers

Tilt and turn windows (Intus)

What are people's experience with tilt and turn style windows? I have not really seen any except for the Marvin one in person. I am looking more specifically into the Intus Upvc vinyl window. I would prefer fiberglass, but the ratings of these windows and the cost appear much better then Inline and other similar windows.
I am a little apprehensive of the turning part coming into the room, being in the way and such. Also are they fairly stiff and stay in place or do they tend to swing more freely like a door?

In Green products and materials | Asked By Jesse Lizer | Apr 26 12
4 Answers

Indoor dryer vent kit?

Does anyone have any feedback on indoor dryer vent kits? Are they a good idea/bad idea? I have a electric dryer for our new house we're building in New Hampshire, but would like to avoid putting an additional hole in the wall if I could. If I didn't already have a dryer, I would likely have gotten a condensing dryer that doesn't require venting.

In Mechanicals | Asked By Scott McCullough | Nov 13 12
1 Answer

Duct-free bath fans?

Does anyone have experience with these?

Do they satisfy the IRC 2009 code for a powder room (just toilet & sink)?


In Building Code Questions | Asked By Kevin Dickson, MSME | Nov 14 12
2 Answers

Framed basement wall - what sheathing to use?

Hi, my builder proposes the basement end wall (10 ft. high) to be framed and covered with stucco to match the concrete side walls. He says to frame it vs. using concrete may cost a couple of $thousand less. The basement will be uninsulated and unheated.

Problem is what to use for sheathing that doesn't offgas. That excludes OSB and regular plywood. DOW SIS? Marine grade plywood? Advantech? I guess the same goes for the unvented attic sheathing, but maybe not as much of a concern (blown-in FG there). Does anybody have any other suggestions? Thanks much.

In Green products and materials | Asked By Ed Siff | Nov 10 12
8 Answers

What kind of rigid foam insulation should I install over existing plaster walls before installing new sheetrock?

I have an older house with very little insulation and lots of cracks in the plaster. I would like to insulate by putting a layer of foam board over the plaster, and then covering the foam board with sheetrock. Are there any problems with doing this? I want to use a foam board that is green with no off-gasing.

Thank you,


In General questions | Asked By Paul Smith | Nov 11 12
3 Answers

Water and Polyiso Foam Sheathing

If I were to use polyiso sheets to insulate a basement wall and the basement eventually flooded, what would happen to the polyiso?

Also, I'm considering using polyiso sheathing on a new house for the 1st time instead of XPS. What happens to the edges of the polyiso when exposed to rain (potentially heavy rain or days of rain) while under construction?

Bruce Miller

In Energy efficiency and durability | Asked By Bruce Miller | Nov 12 12
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