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4 Answers

Opinions on a wall system

Hello. I would appreciate any thoughtful opinions on a wall system I am looking into.

In Green building techniques | Asked By David Sol | Apr 16 17
18 Answers

DensGlass sheathing and rainscreen materials


Other than not holding siding fasteners, what are the downsides of using Densglass instead of plywood sheathing? A (modest) price difference? Is taped Densglass less of an air barrier than taped plywood?

In Green products and materials | Asked By Domenico Perrella | Apr 11 17
7 Answers

Patio insulation

I live in Florida and enjoy sitting outside on my roofed patio. However, during the summer the heat radiating through the roof is intense. Do you have a suggestion about the best way to slow or stop this radiant heat coming through the ceiling of the patio?

In General questions | Asked By Bob Ross | Jan 30 16
3 Answers

Insulating old 2x4 walls with rigid insulation

Our home is located in western Maryland, (zone 4?) and was commercially built to increase profits without regard as to results. It is a 2800 sq. ft. brick faced story and a half salt box style with full basement and set back into a hill. Foundation is essentially a monolithic pad poured without benefit of steel reinforcement of any kind with extra depth along the rear ground level side. Walls are 2 x 4s with fibreglass insulation stapled inside the stud bays. Front roof 2 x 10s have 6" fibreglass as do the upper bedroom ceiling joists.

In General questions | Asked By user-6818892 | Apr 13 17
7 Answers

Best method for air sealing an existing tongue-and-groove (wood) ceiling? Sheetrock is out.

The Home is located in Zone 4 NC. Question #1 Any problems using closed cell spray foam on any

large cracks , in attic at ceiling plane. Then using blown in cellulose ?

Question # 2

Any best method for securing tongue and groove ceiling to prevent cellulose from pushing down ceiling ? Netting etc.

Question # 3

Thought of using Reclaimed Commercial Roofing foam board Fiberglass faced , using cut and cobble

at attic joist bays. Leaving small air gap from tongue and groove ceiling. My thought was it would

In General questions | Asked By Greenconfusion | Apr 13 17
9 Answers

Slab to foundation wall: Air Barrier and capillary break detail with interior rigid foam

We’re planning on insulating our basement walls with 2 inches of Thermax (foil-faced polyiso) rigid foam, installed with adhesive on the interior of the wall. We’ll also have 2 inches of XPS beneath the 4 inch slab, and would have these different types of foam connect right on top of the footer, similar to the detail shown at:


In Green building techniques | Asked By William Costello | Apr 12 17
4 Answers

Minisplit outdoor unit placement (with pictures)

I have a few options for install locations for my two 18K btu minisplits. My installer is willing to go with any location I want, however it is going to be cheaper and easier to go with options 1 or 2 since they have access to the crawl space.

For aesthetics, I would prefer to go with either options 1 or 2 as well. I just do not want to cause any issues with efficiency due to the units being too close. Also, the air conditioner in the picture will be gone as well.

What are your guy's thoughts? Thanks!

In Energy efficiency and durability | Asked By Justin Serr | Apr 11 17
4 Answers

Semi-controlled conditioned space?

As we move toward installing closed-cell foam in our attic rafters and gable walls, the choice has come up as to how much of the old fiberglass insulation under the attic floor we want to remove. Obviously it has to be taken out in the area where the roof meets the floor to enable an airtight fit by the foam. Ordinarily making this a conditioned space would entail keeping the temperature of the new space as close to the floors below as possible.

In Energy efficiency and durability | Asked By David Goldman | Apr 12 17
6 Answers

Cold Access Room - Gaps in Air Barrier

** Re-posting to the proper Q&A category **

Hi -

In Energy efficiency and durability | Asked By Joe Duchek | Jan 16 17
4 Answers

VOCs in cabinetry conversion varnish

Hello - we are building a home (Zone 4C) and I asked the cabinet maker for a data sheet on the paint they will be using. It is a Rudd conversion varnish with a VOC level of ~500 g/L (<0.1% formaldehyde by weight). That seemed high to me, so I looked up the maximum allowable in the U.S. for conversion varnishes, and it's 725 g/L. I also searched for the VOC level of conversion varnishes sold by Benjamin Moore and Sherwin Williams, and their VOC levels were comparable to Rudd. Should I be concerned?

In Green products and materials | Asked By Mike Dominic | Apr 12 17
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