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8 Answers

Antique house #1: Cedar Roof

I will likely be taking on a crazy project in the next few months - buying an old house in Rhode Island, and improving it, on speculation.

The general scheme is to
--Do minimal work on the older (about 325 years) portion of the house,
--Expand/rebuild the newer (about 115 years) section with modern kitchen, baths, windows, etc.
-- Remove ugly garage, breezeway, and dormer.

In General questions | Asked By curtis betts | Sep 30 15
6 Answers

Insulating a flat roof in Chicago

I have had continued problems with my flat roof on our 10-year-old 3-unit building. This will be the 3rd time having to do major work.

The ceiling below has about 8 inches of blown in insulation with an 8 inch or so open space above. All of which is within the engineered floor joist that should allow for air flow.

On top of the joists is the main roof deck and on top of the deck is an additional deck that is sloped with the roof membrane on top. The wood is completely rotted out but the main deck appears OK.

In Green building techniques | Asked By Andrew Rothstein | Sep 16 15
2 Answers

Can I use Durarock for exterior sheathing behind a stone Face?

I am building a garage with 2X4's spaced 16" on two layers of block in zone 5, only a stones through from zone 6 in upstate NY. Most of the walls will be sheathed with 7/16" OSB covered with tyvec, a coraplast rain screen, and sided with various LP smartside products. The inside of the stud bay's for now will not have insulation, yet I plan on using either fiberglass batts, or blown cellulose and sheet rock in the future to finish of the inside. Also at some point I plan on using a small wood stove to heat it periodically to thaw out cars and other things.

In General questions | Asked By Dillon Vautrin | Oct 2 15
1 Answer

Are there any pre-designed house plans that feature ICF walls & SIP roofs?

Looking to see if there are any plans out there that feature ICF walls and SIP roofs? Or is this something that has to custom designed by an architect?

In PassivHaus | Asked By Peter L | Sep 29 15
12 Answers

Bleaching mold on sheathing?

I'm building our house in Wisconsin, where we had a very wet June with 10 inches of rain while framing. The interior side of our 1/2" plywood sheathing has dried but has developed spots of mold. I'm considering misting it with a bleach mixture and letting dry well before insulating, rocking etc. The finished wall system will dry to the exterior, with 3" of Roxul Comfortboard IS on the exterior and Roxul comfort batts in stud cavities.

Any opinions on whether this is necessary? If yes, how strong should my bleach solution be?

In General questions | Asked By Edward Krause | Oct 4 14
33 Answers

Why is there condensation on the return ducts and mold in the attic as well 60% humidity throughout the home?

This home has since been remodeled, including all new metal duct work and insulation. The issue that we need to resolve is the high humidity in the house at about 60-65% even though the unit is running efficiently. There is quite a bit of condensation on the return ducts in the attic as well. We have had two reputable Heating and Cooling Contractors come to assess the situation to no avail. The owner attempted to contact the original Mechanical contractor, but has not been able to speak to anyone yet.

In GBA Pro help | Asked By Jimmy Miller | Sep 1 15
12 Answers

Thermal Break In Stud Walls


Just found this site 2 months into a renovation of one part of our 45 year old home. We have taken the main floor of the house back to stud/rafters and are now at the insulation stage. The original plan was Roxul with a vapour barrier in the walls with blown in ceiling, but we decided to go with 2lb closed cell foam in the walls to try and close the gaps and make the space more airtight and comfortable.

In Energy efficiency and durability | Asked By Richard Heatley | Sep 30 15
1 Answer

insulation type, etc.

hi all,

i have a semi-detached brick 2-family home in brooklyn. 20' x 65'. tenants are on the top floor and we occupy the first 2 floors. our ground floor is about 3 feet in ground on 3 sides and at grade in the rear. we are renovating and intend to put 2 full bathrooms and 3 bedrooms there, in addition to the laundry and utility room. we recently install a navian ncb240 which currently serves our dhw and baseboard radiators for both floors (tenants have separate boiler).

In Energy efficiency and durability | Asked By josh millis | Oct 1 15
1 Answer

Sub-slab condensate drain

This article mentions running a condensate drain for a mini-split to a leaching system under the slab, or tying it to the radon pipes. Is this a common/recommended technique? If tying to a DWV system risks leaking sewer gas through a dry trap, doesn't this system have the same risk for radon?


In Green building techniques | Asked By John Ranson | Sep 30 15
28 Answers

Rhode Island remodel

My wife and I are in the process of purchasing an 1100 sq ft 1978 ranch in western RI (zone 5A). The existing house sits on an ~800 sq ft unfinished basement with the western (24') and northern (36') walls above grade/walk out.

Our plan is to finish the basement at the kitchen/living areas and re-model what will then be the 2nd floor as 3 beds, 2 baths, a laundry and a study.

In General questions | Asked By Ben Balcombe | May 5 15
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