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3 Answers

Dear GBA readers,
I'm starting the process of finding a roofer who can add up to 6 inches of insulation on top of the roof. I have an unvented cathedral ceiling in the attic, with rafters filled with mineral wool. I would like to get a clearer picture of what is involved before describing my needs to prospective contractors.

In General questions | Asked By Hari Kamboji | Apr 10 14
13 Answers

Im redoing my partial basement, to make it all into usable living space, which involves digging out half of it and removing a current half slab to increase headroom, and adding to the foundation/footing as needed. Is there any real reason to pour a slab after this is all done?
I would love input from someone who has put a vapor/water barrier, some foam insulation between 2=4 sleepers, and then used some form of wood flooring that would work for higher humidity situations.

In Green building techniques | Asked By rob rosen | Apr 5 14
10 Answers

Hi everyone,

In Energy efficiency and durability | Asked By Nicholas Brown | Apr 4 14
6 Answers

I appreciate any help I can get on this: We recently built an energy-efficient greenhouse and the mason just finished building the concrete block raised beds. We need to seal or install a liner inside the raised beds to keep water (from the soil) from leaching through the seams of the concrete and we also need this sealer/liner to be safe for growing edible plants and trees (i.e. not leaching contaminates into our soil). We will mostly be growing fruit trees but plan on growing vegetables as well. Can anyone give us advice one what products would be appropriate?

In Green products and materials | Asked By Leah Marshquist | Apr 10 14
7 Answers


I am designing a small commercial building for a client in climate zone 5A.
The design has two thermal challenges I am looking to get opinions on. For brevity, I will address only one here.

In Green building techniques | Asked By Eric Whiting | Apr 10 14
2 Answers

Hey everyone,

I am designing a small commercial building for a client in Climate Zone 5A.
The design calls for largish overhangs on the south facade, and I am playing around with some ideas on how to build these.

Traditionally, the interior structure (in this case, timber frame) would bear on the interior, and the top chord of the truss or rafter tail would cantilever out to create the overhang. However, with this design there is automatic thermal bridging, and the building envelope is compromised.

In Green building techniques | Asked By Eric Whiting | Apr 10 14
2 Answers

Much like the title says, I am having trouble finding appropriate flat roof vents for two spot ERV units I am installing. I don't think I have an issue with the exhaust, as I would think that any roof vent would work. I am having more trouble trying to find a roof vent for a flat roof for the intake side, which as I understand it, would need to not have a gravity damper on it.

In Green products and materials | Asked By Wayne Weikel | Apr 9 14
9 Answers

We are building a new house and in research insulation options I decided on dense-packed cellulose. My builder seems very opposed to it. He uses blown-in fiberglass. He said he had problems in the past with settling. He also thinks the R-value is probably higher with blown-in. Any advice would be really appreciated.

In Green products and materials | Asked By Shannon Kistler | Apr 6 14
7 Answers

How should we deal with Private Rooms?

1. Don't worry about it
2. Seek clients who are not too concerned about comfort
3. Keep bedroom doors open (especially when occupied)
4. Provide Radiant Panels and Don't worry about Cooling
5. Preheat the Ventilation Air and Don't worry about Cooling
6. Undercut the door and pray
7. Provide a Ductless in every Private room instead of the Common Space(s)
8. Provide Transfer Fans between Public and Private Rooms
9. Don't Do Ductless
10. Other

In Energy efficiency and durability | Asked By John Brooks | Apr 8 14
8 Answers

I have a 16 X 28 work shop with a metal roof installed over felt and OSB Sheating with silver radiant barrier on the underside. The outside walls are covered by 7/16 OSB and Hardi Board planks.

I live in South Texas where it gets extremely hot and while building, I added soffits and a ridge vent with gable vents to help the air flow but it still gets fairly hot inside. I will install an 8 ft interior ceiling made of sheet rock and for the walls, I will use 7/16 OSB.

In Energy efficiency and durability | Asked By Leonard Lyle | Apr 8 14
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