Q&A: A Forum for Green Building Experts and Beginners

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3 Answers

I replaced an incandescent light fixture with a CFL fixture that uses a GU24 lamp. This is a hallway fixture so it's controlled by two separate switches (3-way) that are backlit when off.

Everything works as expected, but I noticed that CFL lamp flickers slightly after the fixture has been turned off.

Is this typical or have I wired something wrong? Any advice is greatly appreciated!

In Energy efficiency and durability | Asked By Trung Phung | Dec 24 11
2 Answers

Came across something interesting. A new insulated door had been installed. Its a mobile home door, so its frame is aluminum. The condensation was dripping from the inside of the frame. Is there a detail for this type of door, to prevent thermal bridging, or condensation?

In General questions | Asked By shane claflin | Dec 23 11
8 Answers

Hi GBA community!

I am having a difficult time comming up with the ideal wall construction(detail) using 2x6 timber for a build I am doing this spring. There are 5500 HDD here in Northern Ontario - Canada.

This is what I have so far...working from inward to out
-1/2" Drywall
- 6mm poly
- BIBS (fiberglass) in the 2x6 cavity
- 2" XPS (non taped)
- 7/16" osb
- house wrap (wrb)
- Siding and Stone

Couple of questions:

1. will the osb cause me any issues?
I have it there to affix my siding and for structural support (or can it even do that over 2" foam affixed to studs)

In GBA Pro help | Asked By Brian Krmpotic | Dec 19 11
4 Answers


In Green products and materials | Asked By MICHAEL COUCH | Dec 20 11
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
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