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64 Answers

Do I really need 4 minisplits?

My wife and I own a lot in a development in the Pacific NW (Zone 4c), and we are planning to build our retirement house on it. We have never built a house before. Our projected house (which we designed ourselves) is 1,833 sq. ft. on one story, a modified California-style bungalow, as simple in geometry as we could make it.

In General questions | Asked By Gordon Taylor | Jan 23 12
54 Answers

Dealing with mold on the inside of OSB sheathing

Zip code 53951, south central WI, zone 6a.

Working in non-perfect situation - occupying unfinished house and can't afford to finish it up in timely manner. Heated by central air furnace with supplemental wood burning stove heat. Plan is to finish walls first and after we can afford to do the infloor heat, finish ceilings (2 stories to do)

Moved in early October, found mold about week ago (late February), when moved some fiberglass for new electrical box. Still recovering from the shock...

Here is wall profile, all new materials:
- (no siding yet)

In General questions | Asked By Nick Zees | Mar 3 13
3 Answers

Insulating a cathedral ceiling

I am trying to find an effective way to insulate a cathedral ceiling (with collar ties) in zone 5 south of Chicago. I have read many of the postings and have gathered much information, but am still hesitant due to the moisture drying to one side issue.

What I have is 2x6 rafters on a 4/12. I am doing a complete remodel and plan on removing the existing drywall and insulation. I want to verify the existence (or not) of ventilation chutes from eave to ridge.

In Energy efficiency and durability | Asked By jon cypert | Nov 25 11
2 Answers

Insulating a crawl space

Situation: Existing uninsulated very shallow crawl space with a concrete floor that doesn't have insulation or vapor barrier under the slab located in climate zone 6 just a few miles south of the "border" for climate zone 7.

My plan is to insulate the space with 4" on the walls and 2" on the slab of type 1 EPS and then cover that with about as much blown cellulose as I can fit in the space (about 2' high). It is empty space - no mechanicals of any sort in there.

In Energy efficiency and durability | Asked By Greg Smith | Oct 4 13
4 Answers

Dryer vent in air-tight Passive House

I am building a house in the Seattle area to Passive House standards. After spending countless hours sealing every crack, seam and penetration to achieve under 0.6 ACH, creating a 4 inch diameter hole in my air barrier pains me. I've looked into condensing dryers that are used in some European Passive Houses, but they seam to take much longer to dry and use lots of water. Since I will be installing a vented dryer (unless someone can come up with another solution), are there ways to make the dryer wall vent more air-tight when the dryer is not in use?

In PassivHaus | Asked By Gerald Blycker | Nov 21 14
29 Answers

Trusting a heat load calculation & downsizing...

I'm replacing my furnace & had a Manual J-based heat load calculation done by a reputable person using the Rhvac software. I paid a sizable amount of money for this heat load to be done - but I was tired of going to contractors who relied on rules of thumb & made educated guesses based on experience. I just want the concrete numbers to back up any claims.

In General questions | Asked By Jeff Watson | Nov 15 14
2 Answers

Is this a sufficient wall system for my basement?

Zone 6a. One inch foundation plus type two eps foam adhered directly to concrete with PL. Seams taped and corners spray foamed. 24 oc studs with r20 fibreglass Batts. Should I include a poly vapor barrier before drywall? I've been told to omit this as the foundation plus should be sufficient enough for a vapour barrier. Also should I spray foam the small portion of exposed concrete at the top of the wall between the type two foam and the Sill plate? I should also mention it's an eight foot foundation with about six and a half feet below grade.

In GBA Pro help | Asked By Mark McKenzie | Nov 20 14
1 Answer

Mitsubishi M-Series New FH vs. Old FE models

We're in the market for an M-series heat pump and dealers have been quoting us the older FE models rather than the newer FH models. Is it a mistake to purchase an older model that will probably be discontinued sooner rather than later? I would think so. Thoughts? Thanks.

In General questions | Asked By David Greenberg | Nov 21 14
3 Answers

Mod-con forced hot water system that squeals

My plumber recently replaced the boiler in my small 3-zone Colonial with a Lochinvar WHN-85 boiler with a Lochinvar SIT 40 indirect water heater. Seems to work well, but I've been having trouble with noise.

First, the boiler occasionally emitted what I called a foghorn noise out of the exhaust pipe (the plumber opined it was a French horn). The solution was to tune the mixture to the rich side of the specified range (i.e. more gas per air, and more CO2 in the exhaust), which made it go away.

In Mechanicals | Asked By Daniel Griscom | Nov 19 14
5 Answers

We ran into a few deep uninsulated roof channels

Too little to have a cellulose sub. Are you better off packing them full with pieces of fiberglass batts, or risking air movement by sliding a loose batt down? What is the R factor of hand-packed fiberglass? Thanks.

In Energy efficiency and durability | Asked By Robert Mason | Nov 20 14
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