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7 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
0 Answers

Foundation capillary break & waterproofing

My wife and I are building a small home (First Day Cottage) on a full foundation with a walkout on the downhill end. I read about having a capillary break between the footing and foundation wall and it makes sense to me. When I asked the concrete contractor about it he said he's never done it (though he did remember one other customer who asked about it a couple years back). I get the impression they won't leave me much time to do it myself between pours.

Asked By Martin Frank | Jun 30 15
51 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
42 Answers

Spaceloft my only option?

Needing to get all the R value I can get in a limited space. From the cob webs you can see that this is an old house. Recently installed Cedar shakes with felt underneath over the 2x4 studs or mini rafters...
I think they call this a skip sheathing install of the cedar roof?
So, 3.5" is all we have but we'd like to get to an R50 or thereabouts in our upgrade of this 1925 built home in Climate zone 4C.
Spaceloft seems the only option. With an R10 per inch. It comes in 10 cm thickness, 0.4".

Asked By Jan Verschuren | May 29 15
10 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
3 Answers

Re-roofing a tar and gravel home

I have a small (approx. 900sq ft.) home with a flat tar and gravel roof. I know the roof is at least 10 yrs. old and I have not experienced any issues within the house from leaks or whatnot. I have however noticed that the overhangs of the roof that stretch the perimeter of the house at 2 feet, have become soft and fairly weak when stepping on them. They also show some signs of mold on the underneath side of the sheathing. I have not noticed these problems with the portion of the roof that covers the house.

Asked By Jared George | Jun 30 15
10 Answers

Tape exterior XPS insulation and housewrap?

Hello,

Long time follower first time poster.. I have learned so much from this site and appreciate all the knowledge you people share.

We are building a tight house in zone 6 Ontario. The wall stack from inside is as follows:

Drywall
2x3 uninsulated service wall
Membrain
2x8 stud wall filled with dense pack cellulose
Cross bracing for lateral strength
2" XPS on exterior
Tyvek WRB
Furring Strips (airgap)
Hardiboard Siding

Asked By kyle lamont | Jun 19 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
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
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