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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
4 Answers

I'd rather put 2" of rigid foam on the interior of the rafters than on top of the roof deck.

I have 2x12 rafters and was planning on insulating with dense pack cellulose or rock wool for a cathedral ceiling. Then putting rigid foam on the inside , then drywall. Does this make sense? I was hoping not to vent. Will this work.

In General questions | Asked By Seth Kelley | Apr 6 14
6 Answers

Why are my Willmar Windows (Jeld-Wen) sealed glass units repeatedly failing?

Subject: Willmar Windows Jeld-Wen Ontario Canada

In 1997 we purchased 78 top of the line windows and doors from Willmar Windows, a division of Jeld-Wen. These were "R+10 with Heat Mirror, Metal Clad Wood" windows and doors.

Since the first year there has been a steady rate of seal failures. In 2004 Willmar decided to replace all of the glass units. In 2007 Willmar finally accomplished this.

They were replaced with glass units called Tripane T2SA with "Triple Solar Shield, 2x Low E and Argon". Since 2007 we have had 12 seal failures in these units.

In General questions | Asked By Jane Gray | Mar 30 14
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