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13 Answers

Has anyone constructed a "wood" basement floor over dirt?

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
6 Answers

Safe sealer or liner for concrete raised beds

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

Exterior rigid foam - horizontal furring?


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

Large overhangs without thermal bridging

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

Help finding ERV flat roof vent

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

Can anyone give me their experiences (positive or negative) with dense-packed cellulose?

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
8 Answers

Do I need to reconsider open-cell foam vs. fiberglass insulation?

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
3 Answers

Hot tub room in a 'heated garage'

Hi GBA Pros,

We just got a call from a client who wants to build a hot tub room in their garage.

My colleague sent me this email about it.

In GBA Pro help | Asked By Chris West | Apr 9 14
4 Answers

Is 170 watts normal for compressor heat?

Just put a Mitsubishi MUZ-GE24NA in my home. I checked the standby loss with the inside unit turned off and found that it was drawing 170 watts. I called Mitsubishi and they said it is the compressor heater and it is always on any time it is below 66 degrees.

Needless to say I'm very unhappy to have put in something in that will use around $15 dollars a month before it even produces heat.

Has anybody else had issues like this or do I have a defective unit?

In Mechanicals | Asked By Paul Lennon | Apr 8 14
2 Answers

Roxul and basement wall dynamics

The envelope is pretty good these days and adding more polyiso to
the inside of the basement wall has helped with overall heat loss
a little more, but I think there's still something going on in the
cinderblock wall that's affecting slab temperatures near the edge
and I wanted to float an idea for how I can better deal with that.

This is long, but one needs to understand the background and present
setup. Executive summary: should I insulate just the above-grade
exterior part of a foundation wall with Roxul panels?

In Green building techniques | Asked By Hobbit _ | Apr 7 14
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