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2 Answers

Unvented attic and wall?

Zone 3, 12/12 pitch roof, Galvalume color roof.
Talked to insulation contractor and discussed options.

2x6 walls = Hardie lap siding, 3/8" rainscreen, Tyvek, OSB, air sealing, BIB insulation (R-23), 5/8" sheetrock.

2x8 cathedrial roof, unvented, with total elect units and ducting in kneewall area and spare room in the center = standing seam, membrane?, 7/16" OSB, 2 inch polyiso, membrane or taped joints?, 7/16" OSB, 7 inch open-cell or BIB insulation.
No venting.

Are we getting closer?

Asked By Quinton | Nov 29 15
2 Answers

New house question

After a lifetime in the Southwest, we are building our first home in a Zone 6 area (Northwest Montana near the Canadian Border). I stumbled across this website accidentally, and have read everything I can regarding insulation/ barrier techniques, but was hoping for some clarification.

Asked By Bill C | Nov 30 15
2 Answers

Saving beetle-damaged reclaimed framing lumber

Is there a practical way to make safe beetle damaged framing lumber?

In this case it's 1930's era old growth douglas fir 2x4 rafters, which were removed then stored outdoors. Pretty much all of them have beetle exit (or entry) holes (see representative picture). The wood is plenty strong, but clearly the beetles can (and did) spread.

In theory killing methods include: heat/kiln cooking, chemical saturation, microwave energy like that used for termites, freezing. But in practice, in the San Francisco Bay Area, is this wood compost or fixable? What's the green thing to do?

Asked By Bryce | Dec 1 15
1 Answer

ComfortTherm plastic-enclosed batting above radon retarder sheathing in crawlspace?

I have encapsulated my crawlspace (5-7' tall walls) with proper poly I got from radon mitigation specialist. Everything all the way to band joist is encapsulated. I also have good above code level ventilation going between crawlspace and basement. Basement walls I was able to cover in polyiso, but I don't have large enough access hole to the crawlspace to get even 1/4 size sheets of polysio.

Would attaching ComfortTherm plastic-enclosed batting work in that kind of situation? I am in Zone 5.

Asked By Apollo S | Nov 30 15
1 Answer

Smart MemBrain in Zone 5

As some of you may have followed my other Q&A posts, you may know I have installed the Certainteed brand Smart MemBrain on the interior side of my walls.

I live in Zone 5. My walls are 2x6. Exterior to interior is vinyl siding - Green guard Raindrop 3D wrap - 7/16" OSB - 2x6 studs w/ R-23 mineral wool insulation - smart MemBrain - future 1/2" rock - latex paints.

Asked By Nicholas | Dec 1 15
1 Answer

Insulating unvented roof assemblies

I had read the article here.... http://www.finehomebuilding.com/how-to/departments/energy-smart-details/...

and since 1 and 2 require foam above the roof sheathing which I can't do without redoing the roof which is high expense it leaves 3 and 4. The comment seems to be under the "how much insulation" that "code requires the [closed cell] foam layer to meet specific minimum R-values" in the table. I assume the closed cell based on the air-permeable comment.

Asked By Michael | Dec 1 15
2 Answers

Rescued lumber from 1930s roof trusses: It is treated?

I'm adding a second story to my 1930's bungalow. As far as I can tell it's the original roof trusses -- looks like 2x6s. I'm planning to save the lumber from the roof trusses to use in some other projects. Does anyone know if that wood was treated with any chemicals back in the '30s?

Thank you in advance for any thoughts/ideas/comments.

Asked By Michael | Nov 30 15
7 Answers

Can I leave the fiberglass insulation in place and add 1/2-inch Rmax polyiso to the interior?

I am starting a renovation in a home with T-111 exterior siding, 2x4 walls, 3 1/2" fiberglass batts for insulation. Can I add 1/2" foil faced Rmax on the interior wall and then sheetrock? Is there a better way to increase the insulation/air sealing then what I 'm describing?

Asked By James | Nov 30 15
11 Answers

Pros and cons of Grace Ice and Water compared to Tyvek Drainwrap

If applying a WRB under rigid foam insulation, what are the pros and cons of using Grace Ice and Water Shield compared to Tyvek Drainwrap, in terms of protecting the sheathing, serving as an air barrier, difficulty of installation, flashing details, and any other reason you might prefer one product over the other to serve as a WRB? Assuming that the Grace product is more expensive, do you believe that it is worth the additional cost on a 2,000 square foot home in Zone 5?

As always, any advice or opinions are greatly appreciated.

Asked By James Timmerberg | Nov 29 15
4 Answers

I may need to tear out some insulation

Ok..before I found this site and looked into the proper techniques of insulation I started insulating our basement rim joist/sill plate area because we were working on the house and I was losing tons of heat in this area. I insulated about 30' of the sill plate area with foil backed 3/4" JM insulation doubled up..so 1.5" against the 8x8" sill beam.

Asked By Geoffrey Cook | Nov 30 15
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