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17 Answers

Closed crawlspace with dehumidifier and foundation insulation

I am still in the planning stages of building my new house. I would like a closed crawlspace (I'm in a mixed humid climate) with a dehumidifier and foundation wall insulation. See page 35 (which is actually page 41 on the pdf page counter) http://www.advancedenergy.org/portal/crawl_spaces/pdfs/Closed%20Crawl%20... for a sample design of what I'm going with. I have two main questions about this design choice:

In Energy efficiency and durability | Asked By Michael Geoghegan | Oct 27 14
5 Answers

Roxul comfort board in basement?

I spoke to someone at the Roxul company the other day who recommended the following basement insulation. First, tyvek or similar against the concrete basement wall, then 1 1/4 " roxul comfort board for a thermal break, then a stud wall filled with roxul batts--- sheetrock. Do you see a real problem with water condensing on the concrete with the comfort board and tyvek there? Still seems like too much work but I am curious performance wise.

In Energy efficiency and durability | Asked By Nyle Phillips | Sep 27 12
3 Answers

Drywall directly on stem wall

I've got a 1' tall stem wall in my current design for a house, the outside of the stem wall is insulated with 6" of XPS and will have a moisture barrier on the stem wall. The slab has 3" XPS underneath.

I'm wondering if I should build the walls flush with the inside edge of the stem wall, and then run the drywall all the way down over the stem wall- attaching with glue?

Or is it better to make the drywall end at the stem wall and paint that last 1' of concrete, in case of moisture?



In General questions | Asked By Tom Frisch | Oct 30 14
6 Answers

Brick veneer wall assembly and basement insulation techniques?

I am currently in the process of having a home constructed in Western KY zone 4. The basement floor and walls have been completed.
-walk out basement
-poured walls
-capillary break was NOT installed between footing and wall structure
-minimal external insulation on poured walls (5/16" foam board to protect waterproofing)
-vapor barrier was installed above gravel bed before floor was poured.
-no insulation below slab

?1. how will the lack of a cap. break affect my options for basement insulation (basement will be finished)?

In General questions | Asked By Jeremy McGill | Oct 28 14
5 Answers

Heating bathroom and attached closet

We are beginning a long and expensive endeavor to update a 100 year-old house in the Seattle area and first on the list is updating two small bathrooms. The previous owners of the house installed an efficient Buderus boiler a few years ago, but unfortunately the radiators in these rooms have been long been removed. They are currently heated by a few wall-mounted electric space heaters which I would really like to rip out. Unfortunately, I can't seem to get a straight answer from any heating contractors as to how to heat the space adequately and efficiently.

In Mechanicals | Asked By Corey Vanhove | Oct 28 14
3 Answers

Roxul for insulating and air sealing finished condo


I am trying to decrease air currents and increase insulation in my finished condo. I have large floor to ceiling windows, old baseboards at the base of those windows, and a few columns enclosed by drywall around the perimeter. The columns are loosely filled with pink fiberglass insulation. Air currents are currently coming out of the base of some of these columns and also from beneath some of the baseboards.

Two questions:

In Energy efficiency and durability | Asked By Kalim Saliba | Oct 30 14
1 Answer

Foundation sealing options?

The foundation under my ca 1870s house consists of new and old concrete under the ell, granite blocks under the main house, and a ‘rubble’ wall between the two. A concrete block wall was constructed within a small portion of the granite foundation. This little ‘hallway’ (which has a poured concrete floor) provides access to the breaker box and a small window frame that links the crawlspace under the main house and the (almost) full height basement under the ell. There is a drain beneath the dirt floor of the ell, covered by plastic and rock.

In Energy efficiency and durability | Asked By Rob Shuman | Oct 30 14
1 Answer

I am considering a double wall construction

I am planning to build a house in Charleston, SC (Hot -Humid Climate) and would like to get as close to Net Zero as possible. I think mini-splits will work but dont know if double wall construction is the way to go. Any help would be appreciated.

In Energy efficiency and durability | Asked By Rick Fetter | Oct 30 14
7 Answers

R-35 wall assembly for a 4C Marine climate zone

I am about to build on a 85" rainfall, 6000 HDD and no cooling system (I can withstand a little heat in summer)

I'm thinking of (from outside in)
* 1" wood siding
* 1" of air gap with 1x3" furring
* asphalt paper as WRB and air barrier
* 3" 2pcf EPS as R10 sheathing,
* A 10" double frame wall filled with a total * of R-24 polyester insulation
* asphalt paper as air barrier and vapor retarder
* 3-4" interior wood finish

(see attached image)

In Green building techniques | Asked By Jose Castro | Oct 29 14
3 Answers

New siding/windows and rigid insulation - need some advice

We have a 46 year old house that we have renovated extensively inside and are now planning a major exterior renovation for the spring. We live in Newfoundland, Canada and are in Zone 6.

In General questions | Asked By Chris Stoodley | Oct 29 14
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