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5 Answers

We are in the process of working out a design with a client for a small ~ 600 sq ft inlaw addition. We plan on R-24 walls and R-40 roof insulation. For various reasons we want to use a separate HVAC system, but it's such a small space. We've been looking at mini-splits with two interior units fed off of one exterior (bedroom and living/dining/kitchen) but it seems the smallest such unit is rated for 1200 sq ft. My mechanical installer tells me that the units are variable speed and will compensate for the smaller space. Is he right? Is it overkill?

In Mechanicals | Asked By Daniel McCauley | Jul 11 11
1 Answer

I'm a renter and the hardwood floors in my apt. need to be refinished. My landlord wants a product that will stand up over time (hopefully as well as the high VOC oil polyurethanes she's used in the past). I have chemical sensitivities and need something non-toxic, (I can vacate for a week or two during off-gassing). What is the best-looking, longest-wearing, most non-toxic option?

In Green products and materials | Asked By Sue M. | Sep 14 10
0 Answers

My question is how does it compare with ICF in terms of durability and ability to withstand Hurricane force winds.

In Energy efficiency and durability | Asked By SYED JALIL | Jul 11 11
13 Answers

I'm looking for advice on how DIY-friendly dense pack Johns Manville Spider insulation is compared to dense pack cellulose for a 12" wide wall in a cold climate? In other threads --

http://www.greenbuildingadvisor.com/community/forum/green-products-and-m...
http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...
http://www.greenbuildingadvisor.com/community/forum/green-building-techn...

In Energy efficiency and durability | Asked By Jack Woolfe | Apr 8 11
8 Answers

First things first...fantastic site. I don't know how I found it but it's already proving to be a gold mine of information and I'm thankful to those that maintain this site. I haven't paid for a full membership yet but I'm seriously considering as I get further into my project.

My situation: My wife and I are considering purchasing a historic stone farmhouse that has been gutted and that the current owner began renovating. It has nothing but the original stone shell and a foundation that was poured for an addition to the original (~1800's) stone structure.

In Green products and materials | Asked By Scott Cooper | Jul 8 11
6 Answers

USPTO patents and trademark are available for review, plus a recent ASME technical paper.

http://challenge.ecomagination.com/home/FIXED-COPULA-WINDGRABBER-WIND-TU...

Please contact Brett Krippene at 928-592-9483 or by e mail.

In Green products and materials | Asked By Brett Krippene | Jul 8 11
60 Answers

I noticed an unusual comment in the comment section of this page:
http://www.designbymany.com/challenge/passive-house-for-new-orleans
The comment is about 1/3 down the page (posted May 16, 2011 by Katrin Klingenberg)

In a cooling climate, the delta T is much smaller than in a heating climate, and due to the internal heat gains insulation actually starts to work against you at a certain point. I think anything up to R30ish is doable/defendable for all components, including roof and suspended floor. Beyond that it will only add to your cooling problem.

In Energy efficiency and durability | Asked By John Brooks | Jul 3 11
31 Answers

Does the big white fluffy stuff have the same R Value as the pink, blown in fiberglass insulation? I have heard it is less affective than R2.8.

In Energy efficiency and durability | Asked By Kellye Markowski | Mar 16 10
4 Answers

With or without ducts in the attic, if the mean wintertime attic temps exceed the dew point of conditioned space air by some margin with the roof deck insulation is in place, moisture issues in the attic would be well-controlled, and in summertime even more so, with less access to humid outdoor air to condense on ducts. I've yet to hear/read any reasoning or analysis behind the practice (or of specific instances where leaving it in place caused a problem) yet it seems to be almost a standard with spray-foam installers, independent of climate zone or actual installed R-values.

In Energy efficiency and durability | Asked By Dana Dorsett | Jul 8 11
7 Answers

The equivalent of low solar heat gain is high infrared reflectance. In the winter season, given that 1. there's more heat (infrared) inside the house, and 2. there are more hours of dark than daylight, and 3. the heating contractor has to keep you comfortable every hour (not just the seasonal average), does it make sense to have a window that reflects more heat at you in winter? Similar benefit in summer when you're trying to keep it cool inside.

In Green building techniques | Asked By Don Otto | Jul 7 11
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