Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-08-2012, 07:41 PM   #31
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Rewards Points: 2,000
Default

EPS or XPS


I was surprised to see foil-faced polyiso after the 2" of XPS in the wall, acceptable to BSC after all the studies against in below grade. Other articles of theirs use polyiso below grade when leaving it exposed (without drywall) and change it out before drywall.... The dew point is safe because of so much foamboard that the amount of interior diffusion from the basement is a mute point and the concrete will never get basement air to it.

Gary

__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 01-08-2012, 10:48 PM   #32
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Rewards Points: 1,000
Default

EPS or XPS


ok. got it. john
jklingel is offline   Reply With Quote
Old 08-13-2012, 02:34 PM   #33
Member
 
Join Date: Jan 2010
Location: Fl
Posts: 69
Rewards Points: 75
Default

EPS or XPS


There are two sides to this story, one water making its way through the walls and floor, result a damp surface and water vapor made in the home and condensing on a cold wall or floor.
With the outside water making the surface damp, then exposure to warm air will keep this under control.
With water vapor in the air, then you can either keep the wall surface temperature above dew point, or use a water vapor proof plastic sheet backed by polystyrene to keep the water vapor away from the wall.
The water vapor proof plastic sheet, will fail if the insulation behind it is so thin that the surface temperature is below dew point and condensation will form on the plastic. If the plastic sheet, is not perfectly water vapor tight, due to poor installation, and the insulation doesn't keep the suface warm enough then the water vapor will pass through the plastic and condense on the cold wall/floor.
It is very difficault to fit a water vapor proof sheet over a wall or floor and to get it to work as intended, as the water vapor molecules are very small and they can pass through many things always attracted towards a cold area or surface.
Keeping things warm and avoiding condensation by letting convected warm air flow over them is much easier.
Think of a typical window during the winter.....during the day with warm air flowing, the window stays clear. Close the blinds or curtains at night and the space behind losses its warm air circulation, temperature falls and condensation forms.

Perry525 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.