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19 Answers
Opinions on radiant ceiling heat?

I checked out a building yesterday that had heating mats like this one installed in four areas. Obviously it's electrical resistance heat, and there's an attic above so there's doubtless some loss into the attic, but these definitely make you feel warm, because your head is so close to the heat source. There was 1260 watts of heating installed in this area, along with 576 watts of fluorescent tubes. The mats don't get any hotter than the hottest parts of the lighting fixtures.

Any comments on this type of heating?

Asked By David Meiland | Jan 31 12
6 Answers
Master Green Builder of the Year

Kudos to Michael Chandler
Named Master Green Builder of the year by the NAHB

Asked By John Brooks | Feb 8 12
60 Answers
"What must we say?"

I stumbled on this ancient video recently and heard a sort-of contrarian statement:
"don't EVER say that hot air rises..because that AIN'T so"
http://www.youtube.com/watch?v=S57nIs503fA&feature=results_video&playnex...
(just watch the first 1:30 minutes)

"What happens is that the less dense air is pushed up by the colder air"

I had never heard it put that way ...hmmm.... very interesting

So yesterday Allison Bailes Posts a Blog on the same subject.

Asked By John Brooks | Jan 31 12
4 Answers
REScheck v. Energy Modeling

Hi GBA,
I'd like to start a discussion around the differences as well as the advantages/disadvantages of using REScheck (or COMcheck) and/or an energy model. Although REScheck seems to have been originally written to show energy code compliance cost-effectively, it is often used or mistaken for an energy model - I think primarily because it shows a "% improvement" over code, which is a commonly requested output from energy models when complying with a "above code" program.

I am curious to hear about people's experience using REScheck.

Asked By David Epley | Feb 6 12
3 Answers
What's the difference?

I read on the internet.....Finally, there is a foam in place,cementitious insulation Air Krete that is made from...Yes,Retrofoam made by Polymaster.
My question The salesman told me that Retrofoam excreted gases! I could get Retrofoam cheaper than Air Krete but that it wasn't Green!
Was I lied to?

Asked By Connie Lambert | Feb 4 12
3 Answers
HELP-----Recommendations/cautions for air exchangers?

We are building a passive solar house in northern Minnesota, 15 miles from the Canadian border. We are making it as green as we can -with super insulation, Serious windows & Innotech doors. The shell is done & now we are buying a air exchanger --- the local installer has recommended a Venmar H.E.1.8 ------ 115 to 197 cfm rate of airflo, 2 washable foam filters, Limited Lifetime warranty of core (Polypropylene) with 5 year warranty parts & 94% efficiency -- that is the only brand he sells/installs.
>

Asked By Ann Santo | Jan 23 12
21 Answers
1911 Stack Effect Air Circulation

This Cold Storage Haus is pretty cool.
Super Insulated, Thermal Bridge Free, Good Airtightness, Quad Glazing, No-Foam, No-Electricity
1911
Page 99
http://books.google.com/books?id=plY1AAAAMAAJ&pg=PA99&dq=William+a+radfo...
I think The Air Circulation Stratagem is really cool

Asked By John Brooks | Feb 4 12
2 Answers
What were they Thinking?

From the 1911 William Radford book
Page 101
http://books.google.com/books?id=plY1AAAAMAAJ&pg=PA101&dq=William+a+radf...

Das HuhnHaus

Some more Old School Technology ....moveable insulation, sunken floors, mineral wool insulation and lots more

high res pdf attached

Asked By John Brooks | Feb 5 12
11 Answers
Is 3/4" closed-cell spray foam enough for flash & batt?

I'm building a house north of Pittsburgh, PA in climate zone 6. The house is built with 2x4 walls, 1" blue dow styrofoam sheathing (r-5), and brick outside that. The house is about 3300 sqft. The standard insulation would be r-13 fiberglass batts (which I guess would give the walls a total of r-18).

I already opted to upgrade to geothermal heating/cooling. I was told that I can also upgrade the insulation to a "flash and batt" system for about $3100. They said they'd use 3/4" of spray foam (which would be on top of the blue board sheathing).

Asked By Greg Miller | Feb 3 12
1 Answer
Anyone tried HomeSEED yet?

Just saw this yesterday. Looks like an interesting way to explore alternative strategies to meet energy goals.

http://ekotrope.com/products/homeseed/

Asked By Larry Burks | Feb 3 12
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