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4 Answers

New stucco over foam: cementitious or synthetic color coat?

My New Mexico house is getting a whole new stucco job and the new stucco is over 1.5 inches of EPS insulation, making the wall sandwich look like this outside to in:

Cementitious stucco w/ metal lath
1.5" unfaced EPS foam
0.25" cementitious stucco
Latex paint (ugh)
0.75" cementitious stucco
Single layer of tar paper
Celotex sheathing
2x4 stud wall insulated with faced mineral wool batts
Latex paint

In Energy efficiency and durability | Asked By Nathaniel G | Dec 9 14
4 Answers

Need advice on outside insulation under new vinyl siding

Hi, intending to re-side house with vinyl. 2x4 walls w/plastic under sheetrock and batt fiberglass in walls. Plywood sheathing on exterior. Worried about leaks and trapping moisture. High wind/rain (coastal) area, zone 5 (CT). After stripping existing failing siding, plan to Tyvek house and flash well. Current siding provides R4 (plastic coated fiberglass impregnated foam - looks like board and baton from 1980). Thinking of using Progressive Foam's expandable polystyrene product called Neopor. 1" with R4 and high water vapor permeability.

In General questions | Asked By george baloga | Dec 10 14
4 Answers

Hot basement

I have just moved into a home with a wood burning furnace hooked up to the NG furnace and duct work. When I run the wood furnace (wf) the basement gets really warm. Should I cut a register into the cold air trunk? Thank in advance for any suggestions.

In Mechanicals | Asked By Dennis Krawchuk | Dec 10 14
8 Answers

Mini Splits winning the battle; with PV as a source let's even call it green.

Mini splits with PV are a great option even if not super insulated yet.

Pellet stoves do well, cost as much as a mini split and you have to attend to them.

Oil seems outdated and expensive and smells in old systems and very expensive to install.

Solar thermal there are a few that feel they can justify this, not all.

LP is never going to be as inexpensive as NG, NG is a good value for now, and maybe half a century more, depends on if we start really selling our frack fuel to Europe, which I doubt for now as they have Russia and Russia needs the sales Putin threats or no threats.

In Mechanicals | Asked By aj builder, Upstate NY Zone 6a | Dec 11 14
9 Answers

Cheap thermal imaging camera

It appears that a startup company called Seek Thermal recently has been offering a $199 thermal imaging camera that attaches to Android or IOS smartphones. What little specifications there are look impressive, for example:

  • Reasonably high resolution, 206x156
  • -40C to 330C range
  • Automatic calibration
  • Nearly 10 frames/sec video
In Green products and materials | Asked By Aaron Birkland | Dec 10 14
5 Answers

Best way to insulate a Four-Square attic

Situation: In-laws have 4-square house with uninsulated attic, no roof ridge vents, and plenty of air gaps where original 1x roof sheathing meets attic T&G flooring. Hard to explain but rafter frieze boards exist only at two dormers; all other roof-to-attic floor junctions are a tight vee. I do not know how unvented soffitts were built but they are not accessible from the attic (except at dormers).

In Energy efficiency and durability | Asked By Terry DIY | Nov 30 14
9 Answers

Vapour-permeable peel-and-stick

I'm getting close to the point where I need to turn the plywood sheathing of a double stud wall (which will be insulated with dense packed cellulose) into a proper air and water barrier. One approach I'm considering is to use Blueskin VP alone. Or should I consider taping the seams first?
Any concerns with using a vapour impermeable tape, such as 3M's 8067? I'm somewhat restricted in the products I can use. Prosoco's R-Guard system was my preferred approach, but didn't get the green light from my building department.

In General questions | Asked By Graham Fisher | Dec 8 14
6 Answers

Building a retirement home in climate zone 5B

I plan on doing my retirement home as owner/builder soon.
I have done several homes in zone 2B. Two have been alternative systems.
My question is what is the most effective shell construction type? Effective to me is the most bang for the buck. I'm thinking of a traditional stem wall, possibly insulated on the inside of the block? Exterior walls would be framing. How should it be framed and insulated? House would have a partial loft and pitched metal roof. Should I use trusses?

In Energy efficiency and durability | Asked By r ferd | Dec 9 14
6 Answers

Cathedral ceiling fans and energy efficiency

Hi all,

I just moved in to a house with cathedral ceilings and a wood burning stove (insert) and trying to figure out how important a ceiling fan is. People say it will circulate heat down in the winter (if in reverse) but do folks have a sense of how substantial energy savings might be in gross ballpark percentage terms? Also, is it a benefit in the summer with central air and if so how much? Does the air movement get all the way down to cool in a meaningful way? Do you have to hang it low? Or can it be right at the top. I appreciate any wisdom any of you have to offer.


In Energy efficiency and durability | Asked By Roger Reynolds | Dec 8 14
10 Answers

I'm overthinking windows again... SHGC question

So I think we're close to choosing a local window producer to furnish our windows. Richlin 500 casements offer U values as low as 0.13, very good air seal numbers, are built down the road from us with a short lead time and an economy price. The only downfall that I'm aware of is that they insist on LoE272 glazing for their triple panes. This gives them a dismal 0.22 SHGC. Since I have 36SF of summer shaded, winter exposed, south facing window, I was thinking of going with a different window on the south side.

In PassivHaus | Asked By Ryan Griffin | Dec 4 14
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