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3 Answers

Is there an electric system that can heat water for radiant floor heat, domestic hot water and air conditioning?

I am constructing a new 1000 sq.ft single story with 6' crawl space. Two bedroom, 1 1/2 bath cottage. I would like to have electric solar panels on the roof to offset 90 - 95% of the load. Does this sound doable? I have unobstructed S SE exposure and can fit approx. 20 panels on the roof. This is on Long Island New York

Thank You
Mike

In Green products and materials | Asked By Michael Kinney | Feb 15 13
1 Answer

Spray foam insulation

We will be building a new house this spring and are concerned about using closed cell spray foam insulation as spec-ed by our architect due to potential health risks. Even though the manufacturers say it is non-toxic and safe, there seem to be many people out there who have found otherwise.

Can anyone recommend a product that is safe to use, non-toxic and affordable?

In Green products and materials | Asked By Shepherd Smith | Feb 15 13
9 Answers

Foam board

We've installed foam sheathing on the outside of our house down to the level even with the rim joist. Can we still install foam board on the inside of the house in the rim joist in place of fiberglass?

In General questions | Asked By Aron Robinson | Feb 14 13
13 Answers

Please help me understand this R40+ window design

http://www.jetsongreen.com/2012/05/twelve-glazing-insulated-glass-passiv...

If you read down the article, they've got a "diagonal" model that is supposed to achieve
R113 something ... WTF????

Why aren't we all using this as walls ?

I don't understand what are the principles behind this sorcery,
how could something this shallow achieve such a R value ?

Would like to discuss your ideas about this design ?
any help finding the patents would be good also :)

IF they can achieve anything over R50 in a window, how come aren't we all working

In General questions | Asked By Jin Kazama | Dec 17 12
15 Answers

What sort of vehicle do you drive?

i would be interested to know what kind of vehicles green builders and contractors drive. i am considering changing the type of truck i have but the options seem somewhat limited....suggestions?

In General questions | Asked By erik olofsson | Feb 10 13
14 Answers

Indirect solar heat gain?

Is there any data on indirect ( reflected ) solar heat gain available ?
I haven't found anything using the search box, and only a few uninteresting papers with google.

I guess it would be very complex to calculate vs direct shg,
but is it influent enough to even bother ??

In General questions | Asked By Jin Kazama | Feb 13 13
1 Answer

Strategy for attaching rigid foam on exterior of brick facade

I am looking for the best way to attach either rigid foam or Roxul Comfortboard to the exterior of a brick facade as part of a deep energy retrofit. The first level has brick facade and second level, vinyl siding. Anyone have experience with this?

In Energy efficiency and durability | Asked By Joel Cahalan | Feb 14 13
7 Answers

Phantom load on Occupancy Sensor?

I recently learned (to my delight) that Lutron now sells occupancy sensors that also work with CFL's and/or LED's (Lutron Maestro - http://www.lutron.com/TechnicalDocumentLibrary/3671632a_Maestro_Occ_Sens...).

I would like to use occupancy sensors in our deep energy retrofit (http://delafleur.com/blog/) - but now have the nagging suspicion that in order to operate (constantly monitor environment), they have to draw a phantom load. Question:

- Does anyone know if they do draw a phantom load?
- If they do, does anyone have a sense about the load size?

In Energy efficiency and durability | Asked By Marcus de la fleur | Dec 18 12
3 Answers

Two questions about cost/benefit for insulation and ventilation in a mild climate

Hello all;

I'm in the early stages of designing a house and would love to get some unbiased input on a couple of sticking points between me and the builder.

In Energy efficiency and durability | Asked By Colby Pierce | Feb 14 13
3 Answers

Roof sheathing - TechShield versus Zip System

We are building a 1,600 sq. ft. addition; it is being added to a 1930's farmhouse in the Richmond, VA area (Zone 4, mixed humid). Detail summary: walls are 6 1/2" SIPs, truss roof (see attached file) with partial cathedral ceilings (1 ft. extra heal height for insulation), roof insulation planned is blown-in cellulose (vented attic), conditioned crawl with 2" thermax at interior foundation walls, etc.

In GBA Pro help | Asked By Greg Magnus | Feb 14 13
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