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0 Answers

Would you be concerned about interior Formaldehyde levels with mineral wool

I was looking at using mineral wool batt insulation between studs in a staged retrofit situation. It looks like most of the mineral wool batts available still use a formaldehyde binder.

I wasn't too worried because the home is very leaky right now and I thought that I might "dilute" out the formaldehyde over a few years before I tightened up the envelope. However, I found this article by Dr. Joe http://www.buildingscience.com/documents/insights/bsi-070-first-deal-wit...

In it he shows/states that :

In Green products and materials | Asked By MIke Truxillo | Jan 19 15
2 Answers

Insulating solid brick house

Hello! I've been reading this forum for awhile now and there's so much good information about insulating I don't know which direction to head in. I have a 1950s ranch in Michigan that is under renovation. I currently have most of the walls exposed and wanted to know the best way to go about this. It's a solid brick (like small cinderblock?) house with furring strips and 2 layers of drywall on the inside. On the outside I have furring strips with vinyl siding.

In GBA Pro help | Asked By Jeff Hogarth | Jan 9 15
2 Answers

Wall assembly (Zip R) for mixed humid

Hey Folks,

My architect has planned a 2x4 wall with Zip R 1" foam sheathing. It will likely have batt or blown insulation. I see a ton of Zip sheathing around here, but I doubt much of it is insulated. Should this assembly hold up in my climate 4A (mixed-humid). I particularly concerned about vapor permanence and drying.


In Energy efficiency and durability | Asked By C. Maglio | Jan 10 15
2 Answers

Crawl space solution - Joist rot and drying-in questions

Recently purchased a home in Connecticut with a completely unconditioned, vented crawl space.
No evidence of mold or rot, but some musty odor, and a huge drag on energy efficiency as a fair amount of forced air ductwork travels through the space and air seeps in through the rim joists and vents and stacks upwards into the conditioned space. Space has what I wold describe as a poorly poured rat slab (meaning you can see dirt in certain areas of the crawl that are untouched by the rat slab).

In Energy efficiency and durability | Asked By Chris James | Jan 16 15
5 Answers

Condensation prevention for houseboat insulation

Hi, this is a revisit of the question about trying to prevent condensation and water damage while insulating, but in this case for a marine houseboat. We are talking a 3/8" steel hull, 1" air gap, with wooden frame and "rockwool" insulation bats just under 6 inches deep, then vapor barrier, wood veneered plywood sheeting interior walls. Vessel will have hydronic radiant floor heat using grooved plywood with aluminum face for the PEX tubing, and engineered wood flooring, just under 8' deck to deck height. A 15 ft beam, and a LOA of 92 ft..

In GBA Pro help | Asked By John Shank | Jan 16 15
2 Answers

Finishing insulation on unvented sloped roof with mineral wool over polystyrene

I have an unvented, sloped roof. I cut and cobbled 5 inches of expanded polystyrene into roof rafters, and 3 inches into attic wall studs. Then placed 2-6 inches of expanded polystyrene across the rafters and studs, to create a final air barrier and address thermal bridging.

I plan to cover the expanded polystyrene with 1 or 2 layers of Comfortboard IS mineral wool. Each layer is 2 inches thick. Expanded polystyrene seems ideal except for flammability, so I want to address that with mineral wool.

In General questions | Asked By Erich Riesenberg | Jan 18 15
1 Answer

Fixing a leaky basement duct chase/soffit run properly

I have a small, less than 1000sqft single story house with finished basement heated with a natural gas furnace.

The supply & return registers are on the floor of the main floor, so the ducts run under the floor joists.

Since the furnace room is in the back of the (rectangular) house, there's a soffit that travels to the front of the house, which runs perpendicular to the floor joists. This soffit contains both the main trunk supply and trunk return air ductwork that the registers branch off from. The soffit is enclosed with drywall & the ductwork is not visible.

In General questions | Asked By Jeff Watson | Jan 18 15
5 Answers

The off-grid solar community story was great -- I would love to know more about their insulating window shutters

The off-grid solar community story was great. I would love to know more about their insulating window shutters. Please have the author elaborate on this, as offered in the article.

Please, details on window insulating shutters. For a DIY, it's a great way to beef up privacy and efficiency. Thanks.

In Green building techniques | Asked By Scott Barkdoll | Jan 13 15
1 Answer

Rigid foam on an interior basement wall with exterior rigid foam present


In General questions | Asked By Milan Jurich | Jan 18 15
4 Answers

Foundation insulation transition to SIPs

Hi All-

I'm getting ready to build a couple of single family urban infill homes in Denver, Colorado (climate zone 5b). Local zoning creates a very narrow home (19' wide from exterior finishes) which has me leaning towards using PUR SIPs (4.5" or 6.5") for the exterior walls. The exterior finish will be limestone panels, making using exterior foam and strapping challenging due to the 14lbs per sq weight of the panels.

In Green building techniques | Asked By Christian Butler | Jan 17 15
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