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6 Answers

Relative value of air sealing at exterior sheathing

I am trying to understand the relative value of air sealing at the sheathing. To do this lets consider cost as the benchmark. I realize that there is value beyond cost but this is an easily quantifiable benchmark and the one that seems most resonate with my clients.

Asked By Hugh Stearns | Jul 1 15
30 Answers

It's 2015 and they still build like this...

Brand new build going up in Phoenix, AZ. What you see is completely 100% framed and ready for stucco. The missing OSB sheathing is done on purpose. They do "open framing" and only use sheathing where required. The rest is open 2x4 framing.

They will stuff R-13 batts within the 2x4 walls, staple on some building paper and then put 1" of rigid EPS on the outside and use conventional stucco to finish it off.

A recent blower door test on a home like this showed 15 air changes per hour.

ALL of the duct work and air handlers are installed in the 150F unconditioned attic.

Asked By Peter L | Jul 1 15
1 Answer

Dense-packed cellulose in exterior walls

I have a 100+ year old home and there is currently no insulation in the walls. There is vinyl siding on the exterior and I think it was installed over the old wood siding. I am considering having dense-packed cellulose blown into my 2x4 exterior walls. Am I going to have a moisture problem if I do so? I've read conflicting opinions. I would appreciate any advice you can offer.

Asked By T S | Jul 2 15
2 Answers

Spray foam insulation in attic?

I want to insulate a walk-up attic in a 100+ year old home in climate zone 6. I need to add insulation because there is only about a foot of blown in cellulose under the floor boards in the attic. I don't want to blow in more cellulose because I am thinking about finishing the attic for more living space. I am thinking about having closed-cell spray foam insulation applied against the roof sheathing. The rafters are only 2x4s and I am thinking about firring them out two to three inches to accommodate 5-6 inches of foam.

Asked By T S | Jun 27 15
7 Answers

Did I goof badly? Metal bracket against exterior sheathing

My typical wall section on part of my house is 5" of stone, two layers of 2 1/4" EPS rigid foam, Grace waterproofing, plywood sheathing with 2x4 studs and blown fiberglass between the studs.

Asked By Gary Dick | Jun 30 15
13 Answers

Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?

We are renovating an old railroad station, turning it into a residence and are gearing up to put new roofing on the building. Built in 1888, the building has massive overhangs on all sides and the rafters are mostly 2x6s with 4x6s spaced about 8' apart supported by large brackets. We had planned to use closed-cell spray foam insulation in order to get the maximum r-value in the relatively shallow rafter bays. Also, we want to maximize the available head room in the second floor rooms. The underside of the roof will also be the ceiling with t&g beadboard installed directly to the rafters.

Asked By Jodi Gunderson | May 29 15
3 Answers

Cut and cobble polyiso then spray foam

Hello everyone,

Asked By jason hood | Jun 28 15
1 Answer

Would insulation blown into an exterior wall eliminate bird infestation?

If there is room for the birds who have made golf ball size holes in our exterior wood siding and are raising a bunch of babies in there, could we eliminate the birds and get extra insulation at the same time. We think the birds are the invasive European Starlings, not nice birds.

Thank you for your help, Cathy

Asked By Catherine Rodner | Jun 29 15
1 Answer

Extract current insulation before spray foam in the attic?

I am going to spray foam my attic, underside of roof, and all penetrations with open cell foam to air seal that portion of my conventially built and insulated house. My contractor is telling me I must extract the current fiberglass loose insulation now on the attic floor. While I am willing I can't fully understand the science of needing to extract the current insulation. I am being told there would be two thermal barriers and with AC ducts in the attic the would be a moisture problem.

Anyone have advice or help with the science of this decision.

Asked By David Adams | Jun 26 15
6 Answers

I'm building a home in northern Virginia, climate zone 4

I'm building a home in northern Virginia, climate zone 4. Most of the windows are to the open south, and we plan to shade them for solar access in winter and solar screening in summer. However, it's not practical to shade some of the windows.

I plan to use high solar heat gain for the basement (and exposed concrete floor), and low solar heat gain for the second floor that will have enough heat anyway -- and probably some mixture on the first floor with the master bedroom and living areas.

Asked By Esther Streusand | Jun 26 15
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