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70 Answers

Geothermal nightmare

We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.

Asked By Colleen Nicholson | May 30 13
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.

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.

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.

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

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'

Asked By Stanley F Gilmore | Jun 22 15
3 Answers

Air sealing exterior walls in a benign climate

Hello Martin,
I am removing and replacing the siding on an old Victorian located in Berkeley, CA which I believe is climate zone 3. After stripping off the old layers of siding, we will insulate, install plywood sheathing, (nailed at 4 at eh edges and 6 in the field for seismic stiffness), and then a drainable house wrap and fiber cement siding.

Asked By Craig McCaleb | Jun 20 15
4 Answers

Exterior Foundation Insulation: How to finish


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.

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.

Asked By Mary Schwaba | Jun 26 15
2 Answers

Introducing a new European window importer, Prossimo LLC

Hi Everyone,

My name is Ben Freed. I built a net-positive, 1250 sq ft, pretty (dang) good house in upstate New York last year. I couldn't have done it without my consultant David White of Right Environments, and the amazing community of contributors here on GBA.

I used a few of the European components on my house including, wraps, tapes and triple-pane upvc windows.

I thought all the products I worked with were great, save for one fact: they were too darn expensive.

Asked By Ben Freed | Jun 25 15
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