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13 Answers

Can someone explain the science behind a mid-wall vapor barrier on a double stud wall?

In order to save money, I've switched my wall assembly last minute from using exterior rock wool board to a double stud wall construction. I would like to speak with my county inspector about using this approach to make sure I don't have problems during construction. I'm struggling to understand how I'm going to explain how a vapor barrier on the back side of the inside wall is a good idea.

I'm in climate zone 5, and here is my intended wall assembly:

From inside-to-out:
GWB
Insulweb netting (affixed to stud to hold cellulose)

Asked By Adam Peterson | May 4 16
4 Answers

Cork insulation as finished facade

anybody out there have experience with the expanded cork insulation out there? here's my situation: the higher density facade grade cork is just too expensive to make it work for my application. the standard grade would work, but it's not recommended as a facade. the cork in question would be used as insulation + facade (no siding), but would be in a very low-exposure area, and subject to less weather extremes (it's under a covered area).
i'm trying to get the 'coolness' of cork, plus like the idea of needing less siding material.

any thoughts?

thanks!

Asked By Jonathan Nagar | May 5 16
17 Answers

Slab — thermal break at vehicle roll gate

as I mentioned in a previous post we are putting in a new floating slab on grade in a warehouse building.

the grade has been leveled and sewer drains in trenches and backfilled
then there is a 4-6" layer of compacted gravel and we plan on using a 15mil taped vapor barrier and 2" of taped 60psi XPS on top of that.

for a thermal break we are using 2" 25psi XPS that extends 10" below the slab

there will be radiant installed throughout the building and we are in

my main question is:

Asked By Big Ern | May 2 16
12 Answers

Exterior rigid foam and re-siding project

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

Asked By Howard Gentler | May 2 16
1 Answer

XPS Brands: DOW; Owens Corning; Pactiv/Kingspan?

I would appreciate feedback on the brands of XPS relative to one another.

I'll be installing a double exterior layer next week. Right now I can buy 3/4" sheets of the Pactiv/Kingspan XPS sold by Lowes for $13.57 a sheet (4x8).

Has anyone had any negative experience with the Pactiv/Kingspan foam?

Thanks!

Asked By Bill Daugherty | May 5 16
14 Answers

Comfortboard pricing - Triple $ per R vs foamboard??

Hi all,

Asked By Keith H | Apr 21 16
6 Answers

Sewer vent location

We have a cleanout and sewer vent pipes currently sticking straight up from the sewer lines to above grade level in the area about 5' from the front doors to the building (there are 4 of them, as the house is a duplex). Porch is about to be built, and the area is dug out. The original plan was to have these 4 pipes terminate in the area of a planter that divides the front porch. The porch is 4'10''x12' and has 4 steps on all 3 sides. I hear that these vents may cause unpleasant smell in the area of the front porch. Could this be some kind of substantial smell?

Asked By Lucyna de Barbaro | May 5 16
7 Answers

Interior vs. exterior air barrier

Wondering what the consensus is on the interior vs. exterior air barrier issue is? I am considering this question in light of a double-stud, dense-pack cellulose wall.

Marc Rosenbaum has indicated that he prefers exterior air barriers, because they are so much simpler to execute (no zig-zagging around floor systems, etc).

Asked By Burke Stoller | May 4 16
1 Answer

Insulating two crawl spaces

A friend is having some work done on his old house in upstate New York, Climate Zone 5/6. There are two crawlspace issues.

Asked By Chris Ermides | May 4 16
1 Answer

Townhouse common wall upgrades

I had a kitchen fire in my Gaithersburg, Maryland townhouse (about 20 miles north of Washington DC). The insurance is going to pay to have the walls on the first floor removed and have the insulation replaced. The townhouse was built as part of a quad in 1986, with the main wall facing south, and east and west walls connected to neighbors, and half of my northern wall is connected to my neighbor behind me (the other half faces the central atrium).

Asked By Carl Fosler | May 5 16
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