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21 Answers

Air Scrubber Plus

I am considering installing an Air Scrubber Plus system on Zone 1 for my house. I have a coworker who has installed one and says it has worked great for treating indoor air (particularly cooking smells). I was curious if this system is worth the money? Is it worth it given the lifecycle cost - replacement of the bulb (almost as much as the system)?

Just looking for anyone who knows more about UV bulb filtration, the risk vs. reward, and in particular about this manufacturer and their product.

The link to the air scrubber plus is here: www.airscrubberplus.com

Thank you!

Asked By Shaun Kennedy | Sep 11 14
1 Answer

Wall system for recording studio / home. Vapor questions?

Hello, thanks in advance for your time and knowledge. This site is a great resource.

I am building a home / recording studio in Murfreesboro, TN (zone 4A) and have some questions about my wall system. My plan is to build my walls in the studio as such: vinyl lap siding, 1" xps foam taped at all seams, osb taped at seams, 2x4 walls with rock wool batts, 5/8 drywall, 1/2" sound stop fiberboard and finally one more layer of 5/8 drywall painted. All air sealed as best I can. My question / concern is about vapor.

Does this wall system pose any issues with vapor?

Asked By JOE ROBERTS | May 13 15
6 Answers

Flat roof advice needed

I’m building a carport and breezeway in southeastern Michigan and I’m struggling with construction methodology and products for the proposed flat roof.

Flat roof? I know…Martin's Ten Rules…But… I would like to use all this roof real estate. This roof will cover a substantial portion of my small urban lot and I think, in the future, this could be valuable space. A Small Deck, a Modular Green Roof, Potted Gardens, Solar Panels…

Asked By Howard Road | May 11 15
3 Answers

Spraying foam into stud bays without any kind of barrier

One of my clients has a pre-war home, (Civil War, that is), and would like to spray foam into the stud bays, although there is no barrier of any kind. Just old pine siding nailed to the studs.
I told him first that he should re-naill the siding using splitless ring shank nails to secure the siding.
Without any kind of barrier, I envision foam squirting out between the gaps.
Short of removing all the siding, and installing a vapor barrier, I suggested lining the stud bays from the inside using roofing felt stapled to the studs encapsulating the stud bays.
Any better ideas?

Asked By roger steinbrink | May 13 15
2 Answers

Moisture protection in the crawl space

Does the moisture protection in the crawl space ever need replacing. The one under my house is 12 years old and I was told that moisture protection covers need replacing at least every seven years. Is this true or is it a ploy for business?

Asked By Janet Swope | May 13 15
1 Answer

Are Europly, Appleply or good Baltic Birch plywood available in Vermont?

I am specifying materials for millwork and want to use a good baltic birch plywood so I can expose the edges (rather than edgebanding). What is available and a good/not too pricy choice in Vermont?

Asked By Anke Tremback | May 13 15
2 Answers

XPS & global warming: Updates?

I keep reading that different, less harmful blowing agents than HFC-134a were supposed to come online for XPS foam. Some of these articles date back a few years, and make it sound like the change was imminent. Did any of this ever come to pass? Or are we still dealing with the status quo? The latest article of this kind was on GBA a few months ago. http://www.greenbuildingadvisor.com/blogs/dept/green-building-news/new-b...

Asked By Peter Rogers | May 12 15
8 Answers

Foam under slab details

New residential construction, Zone 4A, slab on grade with attached garage. Three questions:

1. Most builders around here pour the entire slab flat; in other words, no slope to garage door and no step up into the house. Is this an okay practice?

2. I plan to put 2 ½" of foam sheets below the slab for R-10. Is there any compelling reason to continue the foam under the garage part of the slab (there would be no thermal break, the slab would be contiguous).

3. What is the detail for continuing the foam below bearing walls that will be supported by a thickened slab?

Asked By David McNeely | Mar 31 15
1 Answer

Ducted and ductless heads on a zoned mini-split

I performed an energy audit for a homeowner who is interested in a zoned mini-split system.

My question is whether a ducted indoor unit can be used in, say, a master bedroom suite, while a ductless indoor unit can be used in a different zone but with the same outdoor unit; or do all zones have to use the same type of indoor unit -- all wall mounts, all floor mounts, all ceiling insert, etc.?

My second question is whether different zones can use different-btu/h indoor units (e.g., small family room gets a smaller indoor unit than a large living room, etc.).

Asked By Jason Owsley | May 13 15
2 Answers

Radiant floor installer and drywall installer are at odds

I'm having a hydronic radiant floor installed over concrete using Styrofoam-type insulation tiles. The room division walls have not been constructed. The Heat installer says that the frame must be installed prior to the floor heat installation and the drywall installer says that the frame is to be installed on top of the floor material. We are using metal frames. Please advise.

Thank you for your response.

Asked By Ann Dopico | May 13 15
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