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4 Answers

Radon mitigation or ERV for old home with dirt wall basement?

Home was built in 1935 and has 5' dirt and rock walls with a small crawl space above that to the bottom of the upstairs floors which are hard wood when your in the in the basement. Radon measured at 7.7 upstairs above that space. I have a thermopride oil furnace down there also. Radon guys telling me it could cause neg. pressure situation with possible back draft or pull exhaust fumes out of the furnace in the basement area. There is an open walking area the size of a regular sized room where the stairs come down and the furnace and water heater are all easily able to work on

Asked By Scott Van Der Veer | Oct 30 14
3 Answers

Foam insulation question for 100-year-old brick home

The attached illustration depicts the current condition of my wall. The plaster and the lathe is currently removed from the wall.

What I'm thinking of doing is spraying 1/2 to 1 inch of closed-cell foam along the inside of the stud and on top of the sheathing, which will serve as a vapor barrier. The remaining space will be filled with fiberglass insulation, and topped by 5/8-inch of drywall and latex paint.

Another option would be to spray low-density insulation between the brick and wood sheathing by drilling holes in the sheathing.

Asked By Wes Leland | Oct 30 14
1 Answer

Minimum R-values for exterior foam for 2x6 walls

I am building an Arctic entry with 2x6 walls, what is the minimum R-values for exterior foam over my OSB sheeting and house wrap to reduce the chance of moisture accumulation in the walls. I live in Wasilla Alaska, which is zone 7 with about 10,500 Annual Heating Days.

After completing the Arctic entry plan on removing siding and retrofitting all outside walls.

Thanks, all help/info will be appreciated

Craig Steinman

Asked By Craig Steinman | Oct 30 14
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:

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.

Asked By Nyle Phillips | Sep 27 12
8 Answers

A very low addition...

We've been contracted by a repeat client to build a small dining room addition (11' x 12') attached to a contemporary ranch in Maine. Due to very difficult access issues, the addition has to be supported on sonotubes. Bottom of joists (2x10 with fg batts) will only be 2-3 inches over grade.

Asked By ron letourneau | Oct 29 14
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?



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)?

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.

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:

Asked By Kalim Saliba | Oct 30 14
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