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2 Answers

Make-up air for Kitchen Range Hoods

I have a builder that insists on installing a 1200 cfm range hood. What is recommended for make-up air (rate and preferred installation)

In Mechanicals | Asked By Sean Bleything | Mar 2 09
2 Answers

How much R- value do insulating shades/ blinds add to a window?

They are somewhat tight on the top and bottom but have around a half to quarter inch space up the sides. Installers and salesman will tell you they can make hair grow on an apple- should I believe them?

In Green products and materials | Asked By terry nordbye | Feb 28 09
2 Answers

Does it make sense to use ICFs for a frost protected shallow foundation?

I will be building a house near Amherst Ma. in an area with a high water table. FPSF seems like the way to go. ICFs are quick and easy. Is there any reason not to use them for this? Any opinions on insulation - xps or eps? Any recommendations on waterproof material under the slab? I have heard polyethylene gets brittle and breaks down over time.

In Energy efficiency and durability | Asked By Ralph Hill | Mar 11 09
2 Answers

Do I need house wrap under exterior wall rigid foam ?


Do I need to put house wrap ( Tyvek etc) between exterior 3/4 "iso rigid foam (taped)? Can I go naked or just 15 lb felt?

I'm looking at tech drawings on the site and it's not shown.

My guess is not, but why not ask before I go through all this an d do something dumb.


In Green building techniques | Asked By Steve Greenberg | Mar 10 09
3 Answers

High-performance insulation in cathedral ceiling

I'd love to hear feedback on the most efficient and cost-effective way to insulate a cathedral ceiling constructed with scissor trusses (residential construction). I'm considering having the trusses built with 16" or 20" heels and blowing in cellulose to achieve the insulation levels desired. Another option could be spray-foam (closed cell). I'd love any feedback, i.e., pros/cons to each or a better method.

In Green building techniques | Asked By Claire Anderson | Feb 3 09
1 Answer

How green are IKEA products?

A lot people, particularly college-age people, trek to IKEA when it comes to interior design. Given that IKEA promotes itself as a "green" company, what is your take on the products they sell? How green are IKEA products?

In Green products and materials | Asked By Brian Becker | Mar 3 09
2 Answers

cantilever steps

I want to move my steps- inside. I want to have cantilever steps, but can't find any places that make them. As this is residential, it seems to make it even harder to find someone.
Also, I have 6 inch solid concrete exterior walls- will it be safe to attach cantilevers to the wall- I wouldn't think I would use more than a 2-3 inch 'bolt' or other attachment to the wall- would it disrupt the integrity of the wall. I live in an earthberm home and that wall is covered with dirt.

In General questions | Asked By Deb Cirner | Feb 11 09
1 Answer

Changing Gears -- Getting into Green Policy and Research

I have an undergraduate degree in Forest Science and Forestry and a MS in Forestry from the University of Maine. I have always geared my interests and research towards climate change. After moving to San Diego I pursued other interests and have been building residential homes for about 5 years. Recent injuries and economic conditions make this an ideal time for me to get change gears a bit and combine my experiences. There are many aspects of green building that I see as exciting. Do yo have any advice or direction that may be of help to me? GeorgeVisscher@Hotmail.com

In GBA Pro help | Asked By George Visscher | Feb 25 09
3 Answers

Anyone know of a good resource to find an example of a Homeowner's Manual for NAHB's Green Building Program?

I'm looking for a resource, peer group, etc. for help in putting together information for NAHB's Green Building Program. Specifically, in this thread, I'm looking for an example of a Homeowner's manual required to get points in the homeowner education section. It would be very helpful to see some examples and/or templates to base our manual on. Being the first builder in our market to build only green homes has proven to be challenging as the learning curve is great. Any help would be great.

In General questions | Asked By James Fincher | Feb 19 09
3 Answers

Good assembly for cathedral ceiling with blown-in insulation?

This is a hypothetical question but it's something I want to consider for my next house.

I like the natural aspects of cellulose insulation, and I like cathedral ceilings -- what are good ways of making the twain meet? There are advantages to rigid foam, e.g. eliminating thermal bridging (and I noticed that all or almost all of the cathedral details provided on the site use rigid foam), but can cellulose be used and obtain similar performance? How should it be framed?

Thanks in advance,


In Energy efficiency and durability | Asked By Tristan Roberts | Jan 22 09
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