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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?

In General questions | 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?

In Green products and materials | 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...

In Green products and materials | 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?

In GBA Pro help | 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.).

In Mechanicals | 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.

In GBA Pro help | Asked By Ann Dopico | May 13 15
6 Answers

Who remembers Fred Lugano?

Fred over a break time pushed for air sealing years before the rest of us and passive house. Other smart folks missng now... Michael Chandler, and Robert Riversong... Many more right....

In General questions | Asked By aj builder, Upstate NY Zone 6a | Mar 6 15
27 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
21 Answers

Help building a green house or a self sustainable home

I'd like to build my own home or at least design it. But I'd like to know what I'm talking about -- rather not stick my foot in my mouth. I tried to find a contractor but had no luck. They are all out for the money, said I can't build anything less then 200K and that's for cheap materials.

Any help would be awesome. Thank you.

In General questions | Asked By Christine Belanger | May 11 15
4 Answers

ZIP R-Sheathing Climate Zone 5?

I am considering ZIP R-sheathing for a home in Climate Zone 5. The wall assembly would be a ventilated rainscreen as follows (exterior to interior)

1. Hardie Panel siding
2. 3/4" furring/airspace
3. ZIP 1.5" R-sheathing (R6.6 total, 12-16 perms for the OSB, <1.0 perm for the polyiso)
4. 2x6 studs
5. Icynene Low Density (5.5" thick R-20, 11 perms)
6. 1/2" gypsum

In GBA Pro help | Asked By Joseph Yount | May 12 15
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