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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
4 Answers

Trapped moisture on SIP roof

I knew SIPs were the Achilles heel of my 100% engineered house design, But because of inattention to detail, heavy rains at a critical time of my house build pushed water underneath the PVC membrane (applied on mechanically fastened DensDeck) onto my SIP. It happened the night before the adjacent wall could be spray foamed to properly seal off the membrane. Unfortunately, the spraying was later done to the walls and the underside of the SIPs without knowing there was water present.

Asked By Edward Mallett | Jun 29 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
5 Answers

Is my 5000 BTU LG 10 year old window unit significantly inefficient ?

My wife says so, in comparison with similar modern window units. She wants it replaced. The unit runs on all work days, during summer work hours, in my home office in San Antonio, Texas. San Antonio summers are hot, but not as hot as north Texas, as an example comparison. My question is whether efficiency advances in 10 years have made a big difference for small window units.

I tried to search, but every search returned hundreds of irrelevant topics.

Asked By Weldon Cabaniss | Jun 28 15
42 Answers

Attic hot after closed cell spray

Finished attic with 4 foot knee wall , duct located in knee wall to support 2 floor,extremely hot, BASF spray tite 2 inches with spray foam wraped around rafter in knee wall but with Sheetrock on ceiling just 2 in foam In cavity . Suggestions to handle heat issue. Richmond Virginia all attic seal very well thinking heat coming from rafters under Sheetrock. Thermal convection coming from rafters. Worked done in the winter, crawl space also done, house built 1994 colonial 2 story with garage with room above with dormer. Also in crawl space does it really need supply vent and return vent

Asked By Mark hippchen | Jun 27 15
9 Answers

Foam over a concrete floor

I plan 4 - 6 inches of EPS under the slab and now am considering an inch of either EPS or XPS on top with 5/8 or 3/4 tongue and groove plywood or OSB to provide a nicer floor to walk on as well as a warmer floor in the walk out basement. I think this will make it easier to attach partition walls and tile in the bathroom and hardwoods in the sunroom.
Question. .. Is this a good idea, and do I glue the foam (EPs or xps) to the concrete and the sheeting to the foam or leave it free floating?
Any gotchas in this?

Asked By tim brown | Jun 29 15
1 Answer

Choosing a solar (PV) system

Hi, I am completely new to solar and considering proposals from a couple of contractors.

One is proposing a 3.1 kW system of (9) 345W SunPower panels with a SunnyBoy inverter located on a south facing roof.

The other is proposing a 4.2 kW system of (14) 305 kW LG panels with a Fronius Primo 5.0-1 inverter, with panels located on a south facing roof plus on a basically flat roof adjacent to it.

Asked By Nancy Hartman | Jun 30 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

Can I use rigid foam inside and outside a concrete block wall?

I have a concrete block barn I am converting to a living space. I plan to use Insofast 2" EPS panels on the interior which with the block gives me R-12 (Block at 3 and foam at 9). I would like to get a better R value, by adding foam to the outside. Would this create a moisture trapping problem?

How would I fasten the furring strips through the foam and into the block? I was thinking Tapcon screws.

Asked By Philip Faucher | Jun 29 15
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