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2 Answers

Vinyl siding over rigid insulation

I have a multi family project that needs to be resided. Unfortunately we cannot afford to use cement board siding and are using vinyl. Is it possible to attach vinyl directly over rigid anchoring to the sheathing? It doesn't seem to be an acceptable attachment method from the vinyl siding manufacturers. Is it worth installing sheathing over the rigid, perhaps a taped zip system? Thanks.

In GBA Pro help | Asked By Julie | Nov 25 15
4 Answers

Builidng a house from the "Affordable Passive Solar Planbook for North Carolina"

I have the opportunity to possibly build a new house on a piece of farmland. I'm trying to keep the costs down, and I really want to incorporate ways to reduce build cost and future cost of heating the home. I'm in Calgary, Alberta.

In General questions | Asked By Solange Pomerleau | Nov 24 15
5 Answers

Exterior Roxul batt insulation in semi-conditioned space?

I'm building a 10x14 timber frame shed in upstate NY climate zone 5. It's under 144 sq.ft. so doesn't require building permits or inspection. I have pine 2x T&G roofing and 1x wall cladding from a local mill. The building will be used occasionally as a workshop, including during winter. For this reason I'd like to insulate it. I'm grumpy about foam for various reasons including rampant carpenter ants around my property and so would like to use rock wool.

In GBA Pro help | Asked By Michael | Nov 23 15
9 Answers

Spray foam and Roxul for flash and batt?

Hey guys,

I am in the process of finishing my attached garage in zone 5a. It will not be heated year round, just when I am working in there. When it will be heated, I will be using a 240v 6k watt electric heater.

I am torn on how to go about insulating my unvented cathedral roof. I ready that fiberglass batts against the sheathing are a no no but what about roxul? If that's no good either, can I just spray 2" of closed cell and fill with roxul then sheet rock?

In Energy efficiency and durability | Asked By Steve | Nov 23 15
48 Answers

Buyer education versus a good code and intensive enforcement of it

This is kind of a general question. I'm seeing more and more issues coming up on GBA questions and answers regarding shoddy construction that homeowners are having to deal with. I read it recently in Peter L's description of some builders in the Phoenix area. This is most concerning when one is having a new home built, or purchasing a previously built new home, and it has subpar construction.

In Building Code Questions | Asked By Eric Habegger | Jul 21 15
1 Answer

At what temperature should blown foam insulation be installed on a steel roof with 2x6 trusses?

I have a 24x60 pole barn and want to keep moisture from dripping on inside items. It`s getting cold and I want to know at what temperature should blown foam insulation be installed? I`am more concerned with moisture than R value but plan on having 4 inches blown on the roof.

In General questions | Asked By Gordon | Nov 24 15
2 Answers

Brick veneer air gap vents into rim joist in crawlspace/basement

50's rambler with a few additions over the years.
I believe it is cement board siding with brick veneer around the lower base.
Blower door test came in around 4,500 cfm50

In General questions | Asked By B D | Nov 24 15
6 Answers

Does this setup seem sufficient?

After reading many of the articles and comments here, I've been inspired to try and build Passive House insulation and air tightness.

I'll share what I'm thinking so far with the hope that maybe you can direct me in any way. Not necessarily trying to get Passive House certified, but would like to build airtight anyway.

Region: west mountains of Dunlap, TN


In PassivHaus | Asked By Edwin Perdomo | Nov 23 15
14 Answers

Connecting masonry cavity foam insulation to windows and running services in CMU hollow cores


I live just out of Melbourne in Australia. For reference, our climate zone is Cfb (temperate, without a dry season and with warm summers). Annual HDD (Farenheit, with base 65 degrees) is 2,838 degrees. Annual CDD is 450 degrees. It very rarely goes below freezing temperature.

In General questions | Asked By George | Nov 23 15
8 Answers

Best roof assembly on a budget?

Thank you for your website and for the exceptional information available here. I am an active student of GBA and a big fan.

I live in Central East Texas, Hot Humid, and am in process of remodeling a mid-century modern home with low sloping roof lines: 1.5/12 to 3/12. Essentially the entire home and roof assembly will be a vaulted ceiling setup since the interior ceiling is the actual roof deck. Roof is about 50 square.

In Energy efficiency and durability | Asked By Chris | Nov 24 15
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