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3 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
0 Answers

Safe to densepack cellulose into cathedral ceiling bays and polyiso later when re-roofing?

I have very high and steep cathedral roof in my living room and since that addition was built in '78, it isn't exactly built to some great insulation standards. Rafters are 8" deep and currently I have windswept fiberglass there. Have no idea how bad that kills the insulation value, but looking at how fast temps drop in that room gives me sense it isn't good.

Asked By Apollo S | Dec 1 15
1 Answer

Heating and Finishing a basement in a well insulated house

Hi Everyone,

3 years ago I built my own house using techniques from this site, and now I need to finish the basement I built for my quadripeligic brother in law who has to move in with us. The basement is a walk out under a gambrel colonial that is highly insulated. The home construction was doing using dual exterior walls and filling the space with a combination of closed cell spray foam and cellulose insulation. I heat my entire 2000sq foot home with two Mitsubishi mini splits.

Asked By Denis Recchia | Dec 1 15
3 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
3 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 | Dec 1 15
3 Answers

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
3 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
22 Answers

Two backdrafting appliances and dust — Do I need an HRV?

Hello, I have a problem with my house.

1) My house is probably air-tight

2) My water heater backdrafts whenever the bathroom fan is on. It's probably backdrafted every single morning (windows fog up & I feel the warm air at the flue when it kicks on....it only stops once turning off the bathroom fan).

3) Opening specific windows in the basement relieve the backdrafting of the water heater.

4) There was a lot of dust on a return-air duct that was right above the water heater. Another supply duct near the water heater had rust.

Asked By J Pritzen | Nov 26 15
3 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

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
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