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6 Answers

I'm building a home in northern Virginia, climate zone 4

I'm building a home in northern Virginia, climate zone 4. Most of the windows are to the open south, and we plan to shade them for solar access in winter and solar screening in summer. However, it's not practical to shade some of the windows.

I plan to use high solar heat gain for the basement (and exposed concrete floor), and low solar heat gain for the second floor that will have enough heat anyway -- and probably some mixture on the first floor with the master bedroom and living areas.

In Energy efficiency and durability | Asked By Esther Streusand | Jun 26 15
5 Answers

Flush-mount exterior electrical boxes in board & batten with rigid foam and rainscreen?

Good evening all,
I'm still working thru issues involving board and batten over strapping and rigid foam. Now I'm looking into the exterior electrical boxes (for outlets and for lights).
I'd like the boxes to be flush-mounted, with the "rain screen" (do we still call it a rain screen if the strapping is horizontal?) space serving as a conduit chase. That would minimize penetrations of the insulation and WRB- while avoiding surface-mounted conduit.

In GBA Pro help | Asked By Ben Rush | Jun 25 15
3 Answers

Do I need to cover XPS in an attic?

I know codes vary from town to town but I'm looking for the general code requirement/interpretation for this. I have used R-10 2" XPS for the interior of basement walls. I know that it must be covered with drywall or another similarly accepted material for compliance and I have done so. I also have learned that the exception is between floor joists at the rim joist and have benefitted from this exception...wouldn't that be a pain of a detail! I now have to build an enclosure that had never been built for a fire box that protrudes into the attic over the garage.

In Building Code Questions | Asked By Tyrone Powell | Jun 22 15
2 Answers

R-max between drywall and insulated attic

I am interested in using 1/2 R-Max as a thermal break between drywall on the living side and blown insulation on the attic side. I have 2 x 6 ceiling joist and want to blow in r 38 of cellulose insulation. I would put foil side to the drywall and tape all intersections of boards to create vapor barrier.
Anyone ever done this .....this will allow to get some work done in the attic before the blown goes in, and in the end provide a more comfortable room below.The schematic attached is for dow board, but I think R Max will work better due to foil face. Thanks Ralph

In Energy efficiency and durability | Asked By Ralph Vickers | Jun 25 15
2 Answers

What materials to use for underground gutters?

Want advice on matrials to use to make underground gutter to keep water out of basement'

In General questions | Asked By Stanley F Gilmore | Jun 22 15
4 Answers

Exterior Foundation Insulation: How to finish

Hi,

We are building a small cottage up in Maine. Our foundation wall consists of (working outwards) 2" Roxul Comfortboard insulation, 8" foundation wall, and 1 1/2" Roxul Comfortboard again. Does anyone know of any products that are compatible with region 6 climate to protect our outer layer of insulation? Originally after extensive research and calls, we figured a fiber cement board would work, but after further discussion, concluded that it's has a very short lifecyle and a poor decision.

In General questions | Asked By Sarah Payton | Jun 26 15
1 Answer

Is a rubber/foam product a good choice for flooring underlayment?

Hi, Is a recycled granulated rubber tire and high density frothed polyurethane foam product on the market the best underlayment for a 2nd story 1883 farmhouse condo with plywood on top of sub floor where I am installing solid oak hardwood (2 1/4" strips)?
I like it because it has much published technical data that I can show my neighbor in the condo below where we are both interested in sound silencing. I thank you kindly for your expert advice.

In Green products and materials | Asked By Mary Schwaba | Jun 26 15
29 Answers

Radiant floor heating using heat pump?

We live in a Zone 7 area and are building a one story 2000 sq ft on a slab and have decided we would like to heat the house with in-floor radiant. We have been told by HVAC specialists that the best solution would be geothermal, followed by hot water heat pump, electric hot water, then forced air heat pump and electric radiant. We don't have natural gas so that is not an option. Geothermal is out as it is nearly three times the price of the other solutions and this is a retirement home.

In Mechanicals | Asked By John Ball | Jun 19 15
1 Answer

Recommendations for a small bathroom reno

We live in Zone 5 (Ann Arbor) and will be doing a small bathroom renovation in our 1957-built home. Mainly addressing functionality and water management (lousy amateur shower tile from previous owners), but I would welcome advice on expectations or direction we should set with our contractor for insulation, air sealing, and other energy priorities. The bathroom is 7"6"l x 7'w (external wall) x 7"6"h. We are planning for a Panasonic exhaust fan and LED lighting (avoiding cans). We will be replacing most drywall in this bathroom, including ceiling, as we replace the tub and wall tile.

In Energy efficiency and durability | Asked By Phil Ray | Jun 25 15
2 Answers

How to install windows if I build with 2" rigid foam?

Hi. I live in zone 5. I want to build my house not only with 2 x 6 stud walls for extra insulation but also with 2" of rigid foam as that is what the article I read said I would need so I don't have a cold wall.

In Green building techniques | Asked By Ralph S | Jun 24 15
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