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3 Answers

Roxul for insulating and air sealing finished condo

Hi,

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
7 Answers

Steel frame home insulation

Climate zone 2
Ventilated Attic
We plan to use 3" polyiso on exterior walls, taped, with an air gap and steel lap siding.
Plan is to use 6-8" of polyiso on attic floor, and also putting HVAC system in conditioned space.
Radiant barrier on purlins with metal roof.

I'm looking for comments, concerns and advice on whether this amount of insulation is adequate?

or any other thoughts on this approach or things to consider with steel construction.

Thanks

Asked By J B | Oct 28 14
15 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
1 Answer

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
5 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

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
4 Answers

How to seal 4" EPS foam at slab edge (radon concerns)?

Basement concrete 4" slab to be poured on top of 10mil poly, 4" EPS (2 layers staggered seams), and gravel at bottom with perimeter drains connected to vertical radon vent pipe. Building in a high radon zone, will the poly be sufficient covering the 4"x4" foam perimeter strips not covered by concrete at the slab edge? Should I be tapering the foam edge instead of keeping the full width of 4"x4" strips?

Asked By e c | Oct 29 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.

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.
Thanks!

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)
http://en.climate-data.org/location/147654/

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)

Asked By Jose Castro | Oct 29 14
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