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1 Answer

Insulation refit and balancing the insulation.

House located in zone 2A, off the ground ~ 2 feet (1800 sq ft). The house has a sloped metal roof with 2 x 6 rafters on 24 inch centers and 2 x 4 stud walls on 16 inch centers. Currently there is no insulation in the walls or floor and 5 1/2 inches of fiberglass on the attic floor.

Attic Unvented (~R30) 5 1/2 inch fiberglass batt with 2 inches of rigid poly iso foam.
Walls (~R20) 3 1/2 inch fiberglass batt with 1 1/2 inches of rigid poly iso foam.
Floor (~(R13) 2 inches of closed cell foam.
Windows triple pane low e argon gas filled.

In Plans Review | Asked By David McMillan | Jul 28 12
1 Answer

How to insulate a basement wall rim joist that is an inaccessible "cavity"?

Baltimore, zone 4A

In Green building techniques | Asked By richard Ugarte | Jul 27 12
5 Answers

Ooops... where's the air barrier?

Here in WA state we now have blower door testing required for new homes, and they have to meet a fairly lax standard. As expected, a lot of folks aren't clear on what air leakage is and how to build tight. Got a call yesterday from a man with a new owner/builder home underway, insulation just installed, and he wants to know about testing. He intends to put T&G wood on all walls and ceilings. The building inspector advised him that he would need 4-mil poly as a VB if he wasn't going to have drywall with VB primer.

In Energy efficiency and durability | Asked By David Meiland | Jul 27 12
23 Answers

How do I detail unfinished wood rainscreen siding?

I don't like the idea of paint, stain, or wood preservatives. They're expensive, a lot of work, and often toxic. Unshaped, wood boards are available, durable, relatively cheap, and easy to replace. Of all the siding options, unfinished wood benefits the most from a rainscreen, yet is proving to be very difficult to detail.

Two ways of installing board siding in a rainscreen fashion is vertically "board and batten" style, or horizontally as clap boards.

In Green building techniques | Asked By Richard Baumgarten | Jul 24 12
10 Answers

Condensation in wall cavities

I'm hoping you experts can help me better understand the impact of potential condensation within a wall cavity in the following scenario:

In Energy efficiency and durability | Asked By Milan Jurich | Jul 21 12
9 Answers

Air sealing and insulating finished attic space

Hi. I'm new here and would like to start by thanking everyone who shares their extensive knowledge with homeowners like me. I read last year's thread on retrofitting insulation to a 3rd story finished attic with great interest as I have the exact same problem. However, I didn't understand some of the technical aspects and a definitive solution was never determined. The link to that thread is


In GBA Pro help | Asked By Cherylann Schieber | Jul 23 12
2 Answers

Multi bath fan control for exhaust ventilation

I recently read about a system for bath fans that could be programed with the amount of exhaust ventilation required, would calculate manual usage and automatically run the fans to make up the difference. It was for multiple fans and communicated with each unit through the 110v wiring (no data cable needed). I think it was Panasonic and I've searched this site, Panasonic's and Google to no avail. It seemed like a great option to use in conjunction with a central-fan-integrated supply ventilation.
Can someone point me in the right direction to find this product.

In Green products and materials | Asked By Mac Snelgrove | Jul 27 12
1 Answer

Fireplace work around?

The house I'm buying has a fireplace. We will NOT be using it but don't want to take it out, just in case someone still wants one when we re-sell it. So:

do you have a work around for air sealing and insulating at the damper that isn't permanent and can be removed for some future owner?

Thanks in advance.

In Green building techniques | Asked By JoeW N GA Zone 3A | Jul 27 12
7 Answers

Small dental office wanting to install the smallest water heater possible

I have five handwashing sinks and one sterilization sink and took out my 40 gal gas tank heater,Space is at a premium and wondering what would be some good options. The building is from 1968.

In General questions | Asked By Joe Stricker | Jul 26 12
1 Answer

Vinyl windows on exterior foam panels

How do you install vinyl windows on 2 inch exterior foam?

In Green building techniques | Asked By Tucker Spohr | Jul 26 12
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