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2 Answers

Airtight Drywall Gaskets Location

With the Airtight Drywall Approach, using gaskets (Conservation Technology's), I'm wondering where exactly on the top plate these should be stapled to? On the diagrams about Airtight Drywall it is a little hard to tell as the "dot" where they show the gasket being is basically in the corner between the ceiling drywall and the wall drywall for the partition walls.

In Green building techniques | Asked By Nick Hall | Jan 14 16
3 Answers

Wood accent wall

Zone 5b. Spokane wa. concrete foundation walls. 2" of xps, framing with roxul. planning for drywall but would like to have one or two wood accent walls on ext surface. what would be a suitable surface behind the wood planks? the boards will be spaced slightly to give some shiplap look to them. Something black would be best. would like to avoid both drywall and the planks. would 60 min paper work? Maybe a roofing tar paper? inspector has ok'd the assembly with just planks and no drywall and no vapor barrier along the drywall only sections.


In Green products and materials | Asked By Sean | Jan 12 16
2 Answers

Cathedral ceiling insulation and synthetic roofing underlayment

I have a house under construction. The great room has a cathedral ceiling with 2 x 12 rafters. there is a ridge vent for most bays. One or two bays die into a chimney chase. There are soffit vents where possible, but several bays have none since there is an overlay roof (name ?) perpendicular to the cathedral with the associated valley. Those bays could have the sheathing opened at the bottom to allow some air from a conventional attic space to move into the bays (not ideal if worth anything?).

In Energy efficiency and durability | Asked By Bob | Jan 14 16
2 Answers

Electrostatic air cleaner for HRV intake?

I live in an area with a lot of airborne dust/dirt (nearby highway and railroad, among other sources) and have been quite pleased with the Honeywell electronic (electrostatic) air cleaner on my forced air furnace return. It removes significant quantities or dirt.

In Mechanicals | Asked By Stuart Friedberg | Jan 13 16
7 Answers

Does anyone make a barbed fastener specifically made to fasten a sheet of foam to another sheet of foam?

I have an attic knee wall area that I'm insulating with reclaimed 1 lb eps sheets. I ha e hundreds of sheets available. I'd like to use cap nails to secure the first layer of foam directly to the knee wall studs. I would tape foam seams. Since I have a large amount of sheets available I would like to apply 6-8" of foam to the exterior. Is there any device like a push pin that is designed to fasten subsequent sheets of foam to another? Since the foam is non structural it just needs to make a tight connection and maintain grip to the other sheet.

In Green building techniques | Asked By Rick Van Handel | Jan 12 16
11 Answers

Mini split efficiency

After reading the articles, questions and answers on this site, over the past few months, i am convinced and saddened that my new mini split system, installed last fall, is likely ginormously oversized.
2 Mitsubishi FH 09's - 1 in each of 2 bedrooms totaling ~ 400 sf. An FH18 for ~ 600sf. House is 1989 rancher with 1000sf, insulated crawl space, zone 4. Attic insulation is 2 layers R19. 8 double pain Pella windows, 1 double pane slider, standard steel front door. Outdoor unit isMXZ3C0NAHZ. Is there any hope that this system can be used efficiently?

In Energy efficiency and durability | Asked By Julie Mccormick | Jan 12 16
1 Answer

Want to add A-frame type gables (screen room) to existing plan

I have plans to build a Log home that has a 10/12 Roof in design. Want to add a Screen room..in a gabled A frame design to back of house. One contractor says its not good idea, but I have seen MANY attached Screen rooms on the internet....they seem to attach to house by cutting back eaves and building a A frame Screen roof on top of existing roof. One internet site used a "Cricket Roof" to divert water from coming into Screen room from roof.

In GBA Pro help | Asked By Kenneth | Jan 13 16
1 Answer

Floor sheathing insulation

I'm working on a home that has a shoddy plywood floor on joists (some sleepers too). There is no real crawlspace, and no budget to dig one. I am interested in improving the thermal performance of the floor...

Is there any precedent for an insulated sheathing? I Can't figure out how else to improve the thermal performance of the floor. Perhaps just a thin foam underlay and cork flooring and call it a day?

In Green building techniques | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Jan 13 16
11 Answers

Kneewall and radiant barrier?

I recently bought a house in Jacksonville, FL. Part of the attic is finished into a loft with a knee-wall construction. It got quite in the loft last summer relative to the rest of the house, and I'm looking at ways to cool it down a bit.

In Energy efficiency and durability | Asked By Craig | Jan 5 16
1 Answer

Black vapor barrier paper

Hi all,

We will be renovating a guest house that dates back to the 1700s. We'll be abating the lead and asbestos, and the environmental report found "black vapor barrier paper" Chrysotile-70% behind the siding. We had originally thought that the siding was original to the house and dating back to the early 1700s. However, it appears that the asbestos paper may indicate that the siding is from a later time. Does anyone know when asbestos-containing "black vapor barrier paper" started being used in the U.S.?

Thank you!

In General questions | Asked By J C | Jan 13 16
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