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3 Answers

I am building an energy efficient house in Victoria, British Columbia. The wall system is 2x6 construction covered with 1 1/2" XPS for a nominal R-27. The XPS will be calked at the perimeter and all joints taped to form the air barrier. In my municipality the Code requires that the the walls have a rain screen (it is actually a 1/2" capillary break) and two planes of protection against water intrusion. The siding material constitutes the first plane of protection.

In GBA Pro help | Asked By Ross Neuman | Jun 30 11
5 Answers

David Meiland asked for the source of the humidity in my garage that might cause condensation. Must say I'm uncertain. The floor is concrete. There is a floor drain and sink that connects to the sewer. The garage is closed for the winter as we are in Florida except for Christmas so that would limit dryer winter air from entering. Otherwise don't have a clue.

In General questions | Asked By David Pahl | Jul 2 11
3 Answers

Can you recommend a low or no voc wood floor stain and top coat. So far I heard of but do not know anything about Vermont Natural Coating and Hood Finishing. Would like a dark walnut or ebony stain on a new white oak floor.
Thank you,
- Karen

In Green products and materials | Asked By Karen Miller | Jul 1 11
1 Answer

My existing garage door has severe condensation during winter. This is developing heavy mildew on garage front wall and pull-down door to attic. I do not know door manufacturer but door is aluminum and has some form of insulation between front and back skin. However maximum door thickness only about one inch. The garage walls and ceiling are insulated. Will door replacement solve the problem or what else can yousuggest?

In General questions | Asked By David Pahl | Jul 2 11
14 Answers

Can someone describe or link to a good example of a non-vented attic assembly which minimizes or eliminates spray foam insulation. Suitable to a retrofit project -- Min R-38 - Zone 4


In Energy efficiency and durability | Asked By John Nooncaster | Jun 27 11
28 Answers

Or perhaps detail dustbin...
If you have a detail that you think would be beneficial to the GBA community, please post it here with the hope that it may eventually be selected for permanent enshrinement in the GBA details "library."

All climate zones are welcome.
It is a shame when perfectly good details become lost in the "void" of long dead Q&A threads.

I should also mention that this thread is listed under the "Plans Review" category for reference.

In Plans Review | Asked By Lucas Durand - NW Ontario, 7A | Jan 21 11
17 Answers

In the house we're just about to build at times of the year with low sun angle because the south wall is 16ft high and has 120sf of windows & doors the light coming in is sure to strike the back walls.

I'm putting in a concrete thermal mass floor but was thinking of some approaches to add mass into the walls that will get directly lit.

One is to stack bricks in the framing before finishing the walls. haven't done calculations on their mass yet.

In Green building techniques | Asked By Jay Hersh | Jun 24 11
4 Answers

We have a 23 yr. old log house we built in the Adirondacks of NY (zone 6). Lots of snow and cold winters. We are replacing our asphalt shingle roof with standing seam metal so we thought we should also upgrade our roof insulation.

Currently we have cathedral ceilings throughout with 2x6 tongue and groove, felt paper, 2x10 rafters 24" on center, 12" fiberglass batts with prop a vent, felt paper, plywood and shingles.

It is a large (4,700 sq. ft.) complex roof with 2 valleys, shed dormer,2 uninsulated porches, 4 skylights and large overhangs.

In Energy efficiency and durability | Asked By Kathy Hall | Jun 28 11
5 Answers

I'm curious if anyone else out there is having trouble with the Eastern Carpenter Bee?


In Virginia, I'm seeing fairly extensive damage to wood soffit and facia boards (they look like Swiss cheese after years of infestation). I'm also hearing reports about wood siding damage.

These bees are great pollinators, but they also cause a lot of damage. I don't think that pesticides are the correct solution. I'm interested in hearing other perspectives.

In Energy efficiency and durability | Asked By Daniel Ernst | Jun 21 11
24 Answers

Greetings. I have been studying this forum over the past month in the hopes of understanding how to fix the building my wife and I moved into in July.

The house, built in 1930 as a bungalow, was renovated in 2004 with a new second floor and large attic, and then renovated once again in 2009 after it was purchased out of foreclosure. The renovations included replacement of all the windows, but not much else from an insulation perspective. We are located in northern Mass (climate zone 5) and the total square footage is 900 per floor.

In Energy efficiency and durability | Asked By rich cowan | Dec 11 10
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