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9 Answers

Insulating top of basement slab - Is moisture still a problem with a barrier?

Is insulating the top of a non-walkout basement slab floor in climate zone 6 really valuable if the slab has a moisture/vapor barrier beneath it? Goal is carpet on top for most to the space. What happens in the event of water flooding from a toilet or clogged drain?

Asked By BobTheWeekendWarrior | May 4 18
1 Answer

Solarium (a.k.a. sunroom) is leaking - Part 2

Thanks Martin and Peter for your previous answers. I had actually already measured the angle between the house and the glass and sent them to a local metal roof company that's going to fabricate the flashing pieces. In terms of finding a contractor, we have been trying for over a year and nobody is willing or wants to fool with it. I have checked with commercial roofers to try to get their advice and get them to come out but in over a year haven't had any luck.

Asked By Matthew Seabolt | Jun 9 18
7 Answers

OSB as air barrier

I read the relevant GBA article, and the entertaining comments section (which left me perhaps more confused than before. Since that is a pretty old article, I'd like to ask if there is any updated info. What is the latest opinion on it? Were the air leakage failures ever determined to be manufacturing defects or an inherent problem with OSB? My house was built with 7/16 OSB interior sheathing as the air barrier / vapour retarder. I'm finally getting close to putting up drywall, and wondering if I should do anything else before it's closed up.

Asked By Trevor Lambert | May 31 18
7 Answers

Rain Screen: Horizontal furring strips with corrugated metal siding installed vertically

I am installing corrugated metal siding vertically over 1" Roxul Comfort Board exterior insulation, thereby necessitating a horizontal furring strip that can bear the weight of the siding. We originally furred the windows out by 2 3/4" with the idea that we would use 1 x something vertical furring strips to allow drainage, then 1 x something horizontal furring strips for the metal.

Asked By Amy Hazeldine | May 28 14
5 Answers

Flat roof attic venting

My first question is.... can anyone recommend a home energy expert local to me in San Francisco Bay Area (zone 3c)?

My 1100 sqft flat roof has both roof joists and ceiling joists with blown-in cellulose filling the ceiling joist cavity, and about 15" of space between joists. I have 2 soffits (about 6x12" each) on one side of the house, one skylight is permanently vented and overlaps with attic space, and there is a louvre vent in an interior closet (which doubles as access hatch).

Asked By DAVID BIANCO | Jun 7 18
1 Answer

Crawl space remediation

Young, dumb and broke, we built the original part of our house (CZ6) on pressure treated piers over bare ground 35 years ago. The floor was insulated with R-19 fiberglass covered with OSB. A few years later we replaced the piers with a shallow concrete block perimeter wall. The exterior from footing to house sidewall was covered with an inch of poly iso protected by a layer of pressure treated plywood.

Asked By Ron Rosen | Jun 7 18
2 Answers

Sump pump or no sump pump?

We are just breaking ground on our “final” home in Asheville, NC. We had spec’d out a sump pump in our bid, but our builder is saying he almost never installs them and doesn’t feel we need one. We’ve had sump pumps in all of our 7 previous house basements – so we’re a bit nervous about not having a sump pump. Some of those previous sump pumps would run every time there was a hard rain, some almost never ran (primarily when the house had an exposed basement).

Asked By Nancy Broadbear | Jun 7 18
2 Answers

Whole-house water filters

Anybody have an opinion on the best whole-house water filtration systems?

Asked By User-6872033 | Jun 6 18
1 Answer

Attic insulation questions (3 layers of fiberglass batts? Insulating above R60?)

I am in the process of air-sealing, baffling, and reinsulating my attic. The existing fiberglass batt insulation is from 1985 or so and is about 6-8" thick. It is wrapped in a vapor barrier on all sides and has been run between the floor joists in the attic currently. I have been moving all of the existing batts and have been piling them in a corner while I air-seal with Great Stuff foam.

Asked By DrJimesTooperMD | Jun 6 18
5 Answers

Attic insulation of eaveless partial cathedral ceiling


Asked By LongfieldL | Jun 4 18
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