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0 Answers

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 Lutkenhouse | Dec 1 15
1 Answer

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 Nesbitt | Dec 1 15
0 Answers

Smart membrane zone 5

As some of you may have followed my other Q&A posts, you may know I have installed the certainteed brand Smart Membrane 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 - 7/16osb - 2x6 studs w/ R-23 mineral wool insulation - smart membrane - future 1/2" rock - latex paints.

Asked By Nicholas C | Dec 1 15
1 Answer

Rescued lumber from 1930s roof trusses, 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 Caruso | 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
1 Answer

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
6 Answers

Can I leave the fiberglass insulation in place and add 1/2 Rmax 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 DeSalvo | Nov 30 15
2 Answers

New HERS rated home: Issues with Trane XL HVAC heat pump constantly calling for heat

Hello guys. Looking for some advice on our new home . Small custom home completed earlier this year. 2 x 6 walls. Single-story. Designed for energy efficiency from the get-go ...

1792 square footage living space. 9 foot ceilings. 2 x 6 exterior walls framed with California corners and insulated headers and insulated wall leads.

Complete spray foam encapsulation. Spray foam walls. Spray foam roof deck, and crawlspace is insulated with spray foam. Crawlspace is insulated to an R-15, walls R-22, and roofline is considered R-38.

Asked By Wayne | Nov 30 15
0 Answers

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
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