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7 Answers

Interior plywood for earthquake areas — can it replace a vapor retarder?

We are renovating a 1925 Pacific Northwest house, Everett WA, right on the coast. It is earthquake territory here. So it would be good to keep this house up through any quakes we may get, when it can be relatively easily done. We have double studded the kitchen wall now. Making it 8" deep. The north wall became 9" deep. Now we are in low need of any vapor retarder for our climate I understand, zone 4C. Interior air barrier never hurts BUT, and here is my question... Would interior plywood sheathing be a good choice to replace the air barrier, caulking the seams.

Asked By Jan Verschuren | Mar 29 15
18 Answers

Fresh air distribution for hydronically heated house?

Currently have a leaky hydronically-heated house.

I plan on removing the siding, installing blueskin VP peel-and-stick, then 2 layers of Roxul R6 ComfortBoard IS from the roof right down to the footings.

Because this should really improve the air leakage, how should I get fresh air in/out of the house to control humidity / air quality / etc?

Do people run a set of air ducts throughout the house from a HRV?

One of the appeals of using hydronic heating is that sound / dust transmission is significantly reduced.

What would you recommend??

Thanks!
.../j

Asked By John Charlesworth | Mar 26 15
20 Answers

Unvented slanted roof with radiant cooling and NO polyurethane in 4C

We are in Everett WA, north of Seattle, right on the coast, zone 4C. I hope that our location will save us...
We have a low sloping steel, west facing roof. Double, 30 weight felt paper underneath to dampen rain noise. I presume 1/2" plywood sheathing. 2x12" rafters, 11" true depth.
We will install WarmBoard R (13/16" thick OSB with aluminum tracks) underneath the rafters for summer cooling and supplemental heating in winter.

Asked By Jan Verschuren | Mar 11 15
1 Answer

Basement insulation

Hi Everyone-

In the process of having my 1970's basement renovated. Looks like it is simply batt insulation between 2x4's with wood paneling, no drywall. I do not seem to have any moisture intrusion (no stains, mold/mildew smell) but will not know until the paneling comes down and the batt out.

What are my options for insulating this space? I do not want to take down the existing 2x4 frame.

Thoughts?

Asked By Mike G | Mar 30 15
7 Answers

Cold climate (6) standing seam metal roof leak

I have concerns my entire roof is leaking due to improper detailing of my standing seam roof. I also think this discussion could help others who might be thinking of a standing seam metal roof. They are not what they're all cracked up to be. Please look at enclosed photos.

Some details:
I have a shed roof (Structure are I-Joists) with a 3 1/4: 12 pitch. R-60 insulation in cathedral ceiling--"flash and batt." "Flash" is 4-6" closed-cell polyurethane spray foam. Hot roof: Fully Zip taped, Zip sheathing and GAF underlayment. And finally: 1" single-lock standing seam Galvalume.

Asked By David Metzger | Mar 28 15
13 Answers

Alternate cathedral ceiling retrofit

I have a project related to a thread titled "How can I best retrofit and insulate an existing cathedral ceiling?" In my case, the zone 4b semi-arid west texas 1978 home's cathedral area has low density glass batts (or none) along with 1x10 or 12 deck boards over 2x12 rafters. The shingles above this unvented space have some blistering, and I was going to replace them along with resetting two skylight curbs that are incorrectly installed and caused some sheet rock damage from skylight leakage.

Asked By Glen Poklikuha | Mar 27 15
4 Answers

Review of insulation/air sealing retrofit plan...

For a cathedral ceiling, still a popular subject of concern I see. I have gotten advice before and used this site to increase my understanding of many building issues. The ceiling currently, from the inside, has V-groove pine boards, then a 12" kraft faced fiberglass batt, no air sealing. There is a vent channel above the fiberglass of unknown thickness and quality (I ran into the builder and asked if it was 2", and he replied "probably less"). The decking is 3/4" OSB, asphalt shingles above (now at 25 years).

Asked By Howard Gentler | Mar 28 15
7 Answers

Rigid foam roof insulation and polyethylene vapor barrier inside — problem?

Was planning on a r-25 insulated roof deck for a ski house in lower zone 6 NH with cold roof (strapping with plywood) on top of that to help prevent ice dams.
Existing cathedral ceiling is actual 8" rafters framed 24" o.c. with 6" paper faced fiberglass batts. In exploring the original construction (circa 1980) I also found a layer of POLY as an additional vapor barrier....which sabotages my R-25 rigid foam roof plan.....damn.

Asked By Dirk Gently | Mar 27 15
4 Answers

GSHP comparison calculator?

I'm looking for an online tool where I can plug in some basic figures such as EER and COP and compare cost/benefit of two ground source heat pumps. Any ideas? Thanks

Asked By C. Maglio | Mar 28 15
5 Answers

Basement wall fire blocking material?

Martin's basement wall insulation article is a classic that I constantly refer to when planning my basement renovation. The main thing missing from the equation, however, is fire blocking. As I understand it, fire blocking generally needs to penetrate through any foam insulation all the way to the concrete. This presents issues with thermal bridging as well as compromising the air barrier and vapor retarder layers that the foam provides. What's the least bad choice? Mineral wool? Pressure treated lumber? Paperless gypsum board?

Asked By Nick Welch | Feb 6 15
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