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21 Answers

Radon is 9.3 pCi/L even after radon mitigation — Is this OK?

Hi. I am having elevated ( 9.3 pCi/L) radon after mitigation done. I have an encapsulated crawl space ( insulated, air sealed, dehumidifier ) with piping running under vapor barrier-which terminates to an outside radon fan connected with a 4"PVC pipe. Would like to find out if it's Ok to install drainage ( perforated black pipe) piping under vapor barrier ( in encapsulated crawl) for radon mitigation. The piping is spilt off of a main trunk ( no continuous circle) to different sections under the crawl.

Asked By Hotandhumid | Jan 22 18
1 Answer

Condensation on uninsulated ceiling

I have a ceiling above my root cellar which is below ground, attached to my basement via an external grade steel door, outside my homes thermal envelope, and passively ventilated with intake exhaust piping.

Asked By Andrew Katz | Feb 11 18
13 Answers

Alleviating perimeter drain water

We have a sump system with the perimeter perforated corrugated 4" drain tiling flowing into the sump from a connection under our 6" thick concrete floor.

Asked By Murray Hall | Feb 1 18
2 Answers

Using non-flanged windows in new construction

I am looking for advice/detail info for using non-flanged wiindows in New Wood Construction with Fiber cement lap siding. All the Details on this site are for flanged windows.

Thanks very much, Peter Hendrickson

Asked By Peter Hendrickson | Oct 25 17
1 Answer

I am interested in a good way to insulate exterior walls of a pole barn in Zone 5a

I have insulated in between the horizontal 2x6 purlins with 1 1/2 bead board with all joints taped and sealed to framing with can foam insulation. I am considering either fasting another layer of 2 inch pink board with all joints taped and sealed to framing with foam insulation, or having it sprayed with 2 inches of closed cell insulation. I also be framing 2x4 walls around the inside perimeter of the building with no other insulation in the walls with 24 inches of blowing cellulose in the ceilings.

Asked By zz57 | Jan 24 18
8 Answers

Avoid higher SHGC windows?


Asked By user-6994996 | Jan 22 18
6 Answers

Will installing a 12 x 18 inch grille between floors help my forced air flow?

I live in a 1800 ft2 NYC brownstone duplex. The two floor forced air system is inadequate to say the least for the first floor. It is 20 degrees colder on that floor. I have had HVAC professionals in and they have told me that there are NO returns on the first floor at all. All the supply vents are in the ceiling and with 12 ft. ceilings, heated air doesn't descend (despite fans) adequately. One HVAC guy suggested punching a rectangular grill (18 x 12 or larger) through the ceiling of the living room into the dedicated air handler closet in the master bedroom of the second floor.

Asked By Jcryder | Jan 15 18
1 Answer

Vinyl Windows with Synthetic Stone (2)

I posted this question last week, but it appears it was closed. We have Vinyl Windows installed, some with integral J Channel and some with Brick Molding and integral J Channel. On one wall of the home, we plan to instead install synthetic stone. I have been researching how best to use these windows with the stone.

I have contacted the stone manufacturer, and they had zero advice to offer. I also contacted the window manufacturer, and they have been no help either.

Asked By Kathleen J | Jan 15 18
1 Answer

Air sealing an old brick building

I’ve been reading with interest the posts on weatherizing old brick buildings, but I still have some specific questions I hope someone can answer.
I have a circa 1837 brick federal with double wythe walls in central Vermont. The bricks are hard fired with tight mortar joints and moisture from the outside is relatively well controlled. Exterior walls are strapped with 5/4” planks supporting the lath and plaster. Interior walls are the same 5/4” planking with lath and plaster on both sides.

Asked By duanegormanbuilder | Jan 13 18
8 Answers

Elephant in the room (kitchen, in this case)

Mechanical air exchange is rightfully part of every plan in energy-efficient buildings. A lot of effort and no small expense is devoted to choices of HRV or ERV balanced air. The house I am building is 3 bdrm. & 2,000 sq.ft., thus: ((2,000 sq. ft /100) x 3) + (4 x 7.5) = 90 CFM. And this is intermittent, i.e. not necessary during shoulder season months when windows are open (six months here in zone 4A), or during other months when the occupants are working all day or traveling for business.

Asked By David McNeely | Jan 7 18
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