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4 Answers

Long room minisplit installation location?

11' X 30' room. Fujitsu 9rls2h. The specifications shows the flow pattern is long and skinny. Would it be best to install at the middle of the long wall or install at the end on a short wall? There will be ceiling fans at the midpoint and at the point farthest from the minisplit if on a short wall.

In Mechanicals | Asked By Shawn Shumaker | Jul 28 14
2 Answers

I'm upgrading insulation in my 1940s Cape Cod near Washington, DC

A major source of heat loss/gain are the side east and west facing plaster & lathe side walls.

I've measured the temperature of those walls; they stay hotter than outside temps well into the night, and there's 5-10 degree increase as you go up the wall from floor to ceiling. They're actually hotter than ceiling and kneewalls alot of the time. There's also some moisture coming through; the plaster is rotted through under the window apron and there are cracks in the corners.

In General questions | Asked By Tomas Bridle | Jul 28 14
8 Answers

Powered attic ventilator with whole house fan

Hello, I really appreciate this website.

I understand that powered attic ventilators have a lot of problems. But my contractor is suggesting adding one to support a whole-house fan, due to the limited attic ventilation. (I do have some passive ventilation but not quite enough, and the gables are maxed out because it's a flat roof.)

So as long as I always run both fans at the same time, and as long as the cfm of the whole house fan exceeds the cfm of the attic fan, is there still going to be a problem?

Thanks!

In General questions | Asked By Robert Shelton | Jul 25 14
3 Answers

Foundation/floor strategy for a heated workshop in Zone 6A

I am planning a 30'x22' farm workshop in Eastern Ontario, Canada. I want to end up with a level floor suitable for woodworking machines (table and bandsaws, planer, jointer etc) , Floor will be on grade, location is on a small rise and I will make sure there is good drainage away from building. I will place 2" of SM insulation under floor. I will most likely frame double stud walls and insulate with 6" to 7" of Roxul.

In GBA Pro help | Asked By mark godfrey | Jul 26 14
6 Answers

Any way to abate thermal consequences due to required 2" termite inspection gap?

Hi All,

We are using Foamglas for insulating under our slab as well as the slab edges (monolithic slab on grade). It is a requirement to leave a 2" gap above the Foamglas on the slab edges for termite inspections. Are there any options to satisfy this requirement, but not have the thermal gap? Perhaps industrial strength velcro or something :) ?

Thank you,
Stacey Owens

In Green building techniques | Asked By Stacey Owens | Jul 18 14
8 Answers

What is a good, affordable construction detail (in terms of long-term UV and water protection and overall durability) for the popular contemporary horizontal, spaced cedar cladding look?

(Examples of what I am referring to can be seen at: http://vastern.co.uk/wp-content/uploads/2013/03/Splayed-cladding-detail.jpg AND http://www.bartonqualitytimber.co.uk/images/categories/chestnut%20claddi... )

I am not terribly conceded about the cedar: if it is stained all 6 sides with two coats and placed on black painted strapping, then it should handle the elements reasonably well. My main concern is what the substrate behind it should be.

In General questions | Asked By Burke Stoller | Jul 18 14
2 Answers

Tear-down with an existing uninsulated basement: convert to slab on grade?

This question might have an obvious answer, but I haven't been able to dig up anything on google. If I were to purchase a tear-down property that had an existing uninsulated, fieldstone basement, what would be the best course of action to build a high performance house? Fill it in with dirt then to then create a slab on grade? Tear out the fieldstone and use the existing cavity to create an insulated basement (while also hopefully re-using the fieldstone on site for something useful like a wall)?

In Green building techniques | Asked By Ethan Fahy | Jul 21 14
19 Answers

How to keep cool in and heat out?

I am not in construction or an architect, just someone who would like to live in/build a small, comfortable, energy efficient home. I don’t need and could never afford a Passive House. Don’t even know if one would work where I live. I live in the low desert southwest near Phoenix. Living is very different here than in cold weather areas. And very different than Florida or humid areas of Texas. Outside temps over 100F in shade 5-6 months; highs 115F; nighttime lows 95F for at least 2-3 months. Low humidity 10 months. Little or no drought resistant shade trees.

In Green building techniques | Asked By Anneal G | Jun 27 14
4 Answers

Composting toilet in a Passive House?

This is probably only a hypothetical question as I doubt I could talk my wife into a composting toilet but…If we have a tight home with balanced ventilation, and if we had a composting toilet that has a small 5W fan continuously exhausting air - how would we provide make-up air?

In PassivHaus | Asked By Scott Tenney | Jul 24 14
3 Answers

Unvented roof assemblies and roof deck vapor permeance

As a long time visitor and few years member, I have tried to absorb the lessons, opinions, science and conjecture presented here. However, I now find myself confronted with conflicting theory regarding unvented roof profiles.

For my own project, (high altitude, dry, -10 to 90 F) I have regarded the "top" layer of sheathing in an unvented assembly to be essentially in dead space - not exchanging air or moisture - the underside in contact or glued to impermeable insulation, the top side sealed off from all contact with the locally required ice and water shield over the entire roof.

In General questions | Asked By Roger Berry | Jul 24 14
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