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4 Answers

Poly on interior wall

I was talking to a builder who said the key to having an energy efficient interior is to use 6 mil poly on the walls before installing drywall. He said you carefully tape around all outlets and seal off the holes.

We are in Zone 5, and although that sounds like it would be a great air barrier, I fear I would be making a mistake to follow his advice.

I am planning a house build with 2x6 studs and the following details. I will use a cheap vinyl siding, good tyvek house wrap, 3M tape on the seams, 5/8 OSB, 2x6 studs, mineral wool or fiberglass rolled insulation, then drywall.

Asked By Nicholas C | Jan 31 15
2 Answers

Does code require fireproof caulk around electrical boxes & light switches?

We had a blower door test on our house following a major renovation (ACH50 = 4.56 on a 1920s Bungalow, Zone 2A). Several leaks identified, along with my plan to airseal them:

1) Electrical boxes & light switches (photo attached) - Caulk the gap between the electrical box & drywall, add a foam gasket behind trim plate, caulk plate to wall (on inside) & install child safety plugs in unused outlets

2) Base of interior door jams (photo attached) - Caulk

3) Exterior door weatherstripping (copper) - Bend back the copper for a more rigid fit

Asked By Robert Hallenbeck | Jan 31 15
3 Answers

Freeze risk for a heat pump water heater in an unconditioned garage

I have an unconditioned garage with a gas water heater in climate zone 5B. The garage is unconditioned, but insulated (R-15 whole wall, no slab edge or sub-slab insulation), and obviously has some exposed plumbing in it. Right now, the temperature in the garage doesn't get low enough to present a freeze risk, probably aided by the water heater's standing pilot light and hot metal flue. But if I replace it with a heat pump water heater, the unit's going to be continuously cooling the room, right?

Asked By Nathaniel G | Jan 31 15
2 Answers

How do I keep my sheathing dry?

This past summer and fall we renovated a 1950s bungalow in New Liskeard, Ontario (5700 Celcius degree days – that’s 10,260 F degree days if I’m converting correctly). We removed the interior drywall and the existing R6 batts. We also removed the siding, exposing the ½” plywood sheathing. Blueskin SA vapour barrier was applied to the sheathing from the sill plate to the top plate.

Asked By David Baerg | Jan 30 15
0 Answers

Adding A/C to 1918 built home

My husband and I own a 1918 built foursquare home. We currently use a single 8000 BTU window A/C unit to moderate the worst of the summer heat in our zone 4 climate (Minneapolis). We have discussed installing a split A/C system or small duct central A/C system on the first two floors our home. I think I have a good grasp on the split A/C systems but know less about the small duct systems. I like that the small duct systems have less impact on the look of the house. From what I understand, attic installations are fairly common with these.

Asked By Brian Forney | Jan 31 15
1 Answer

Closed cell or open cell foam for rim joist in Climate zone 5A

I realize closed cell foam would provide a better R value, but which density of foam would the preferred choice to prevent condensation on the rim joist itself in our mixed climate zone?

Asked By Gary Brod | Jan 31 15
6 Answers

Radiant floor vs. minisplits?

I have a 800 sq. ft. home in Asheville, NC, and am looking to put on a 550 sq. ft. addition. I have been looking into all options of radiant floor heat vs mini splits for our heating and get stuck between preference and practicality. I am adding three floors with each floor being about 190 sq. ft.

Asked By Clayton Hufford | Jan 29 15
15 Answers

HRV as sole means of controlling interior humidity - fail!

I've got one year of data in my new house, and I'm not pleased with the HRV's ability to lower interior relative humidity. I'm hoping folks with more experience can clarify which is more flawed: my mechanicals or my expectations.

Asked By Andy Chappell-Dick | Jan 4 15
1 Answer

Is power washing a 20 year old cypress siding house with a vinegar & water solution effective?

I am looking for ecological solutions to power wash the cypress siding on my 20 year old house. Using vinegar was suggested to me ~ has anyone had success with using vinegar, or can anyone suggest other ecological solutions?

Asked By Shannon Dancy | Jan 29 15
2 Answers

Placement and selection of the elusive barrier.

Asking for opinions. I'm in zone 7/8. My plan is for a one story earth bermed home set about 3 feet below grade, bermed to varying heights of 3 to 6 feet. Typical treated lumber wall but with 12" double stud walls with dense pack cellulose and 2 inch xps exterior with taped seams.The exterior would then be wrapped with heavy poly as per the PWF specs. My question is " Can I continue the poly sheet protecting the foundation up to cover the entire exterior wall as an air, water, vapor barrier. I would have no barrier on the interior wall since the idea is to dry the walls to the inside.

Asked By Thomas Hoffmann | Jan 31 15
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