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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
12 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

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
3 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
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
6 Answers

New home buyer — metal roof in Maine with no sheathing

Hello all,

I am a first time home buyer and looking into buying a new home. My wife and I have found the perfect home here in Maine, but found out today that the metal roof was attached directly to the perlins. I know typically there is supposed to be sheathing and a vapor barrier in between. I have found information on both sides of the argument, which have led me here. Is no sheathing adequate? How will it affect my energy use? and will it be a condensation issue? Is this ok for a cold climate here in Maine?

Asked By dimitrios maniatakos | Mar 28 15
6 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
17 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
6 Answers

How safe is a polystyrene Styrofoam board for me to use practically?

I bought an insulation board from a local hardware department superstore, and I have concerns of it blocking my vent. I do have a couple of magnetic vent covers over my vent. However I'm concerned about a few factors. My room get's very HOT easily. I especially learned this when the sun rises every morning it shines against my room and burns it up into an abysmal inferno. It's the middle of the dead winter and I'm waking up finding myself soaked in my own sweat. (Gross!) The board has a R of 75 Degrees (F), and like any other Polystyrene material it is combustible and very easily ignitable.

Asked By Mark Granberry II | Mar 28 15
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