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11 Answers


In GBA Pro help | Asked By Mary Ostberg | Dec 21 11
1 Answer

In particular, a school building c. 90,000 sq feet roof Area code 06119

I was told that painting it white will be of benefit.

Also, do you know of any state/federal green building reimbursement policies that could be applicable.

many thanks,


please respond to mark.overmyervelazquez@gmail.com

In General questions | Asked By mark overmyer-velazquez | Dec 21 11
4 Answers

Can anyone help? I had a rear dormer put on my 1956 Cape Cod on Long Island this week. I will put fiberglass batts in my 2x4 walls, but is it better efficiency to use R-15 than R-13?

Also, vinyl siding is next. My installer will leave on the asbestos siding (with tar paper underneath) on the exterior walls. To minimize the existing drafts I asked to place housewrap not only on the new dormer sheathing but also over that asbestos siding, then they will add XPS.

I will cork, seal up interior for drafts. Will the housewrap be detrimental over the existing asbestos siding in any way?

In Energy efficiency and durability | Asked By Jeffrey Kolsch | Dec 20 11
15 Answers

Does anyone have accurate information on how much less energy is used by a HRV ventilation system using a dedicated duct work distribution over a HRV connected into a central forced air furnace and using the furnaces duct and fan for distribution (when the furnace has an ECM motor).

Claims have been made that the dedicated ventilation duct system uses less energy - how much less? What is the payback period when you consider the cost to install the secondary duct system.

In Mechanicals | Asked By Sean Wiens | Dec 15 11
1 Answer

I will be writing an article on an energy retrofit and wanted some feedback. Here is an article I had published in the past. I hope to get comments/criticisms of my writing style and the content so I can improve.

"Business: Getting Certified for Home Energy Audits

by Robert Post

In General questions | Asked By Robert Post S.E. Pennsylvania Zone 4a | Dec 20 11
2 Answers

What is your advice on metal roofing at the beach? Will the salt air affect the metal?

In General questions | Asked By Roaring Fork | Dec 20 11
1 Answer

I have a ~1100 Sq foot ranch with a ~200 sq. foot addition on the back. The house proper has a full basement below it, but the addition has a dirt floor crawlspace below it. Access to the crawlspace is through a small plywood "door" accessed from outside.

In Energy efficiency and durability | Asked By Matt Boutet | Dec 20 11
4 Answers

Hello Folks,

I'm in the process of building a 24' by 30' combination artist's space and workshop in a new post frame building. An 18' x 24' loft creates the second floor. There's a lot of detail on the building here

In Mechanicals | Asked By Patrick McCombe | Dec 20 11
4 Answers

I questioned in a previous thread if a bathroom exhaust fan could suffice for exchanging air in a tiny, but well-insulated and tight 250 square foot dwelling.

Someone confirmed, given the small space, that it should be fine and to put it on a timer as it wouldn't need to be constantly on.

Another said: "assuming that the fan on a timer needs to be cycled on and off frequently (for example, every other 5min interval) during occupancy, to compensate for lack of low-enough cfm settings, how significant of an effect on power draw do those frequent start-ups have?"

In Mechanicals | Asked By Kim Kies | Dec 20 11
15 Answers

I'm planning on building a tiny mobile home a little less than 300 square feet total. I live in Northern WI and want better insulation and better building materials and designs than the manufactured homes. I also need some of common building chemicals out of my home.

In Energy efficiency and durability | Asked By Kim Kies | Dec 20 11
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