Vapor Barrier On Basement Pony Wall - Building & Construction - DIY Chatroom Home Improvement Forum


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

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

Reply
 
Thread Tools Display Modes
Old 01-06-2011, 01:03 PM   #1
hobbsInVancouver
 
Join Date: May 2008
Posts: 10
Rewards Points: 10
Default

vapor barrier on basement pony wall


Hi.

I'm finishing a section of my basement that has a 4' concrete pony wall (below grade foundation) with 4' framing set on top. The framing is set back on the top of the foundation by about 4". I'm planning a new wall flush with the foundation to a new top plate on the floor joists above, no ledge. My question is about the vapor barrier.

The concrete wall will be insulated with EPS then fiberglass in the new wall against the EPS rigid board, so the EPS will act as a vapor barrier against the cold wet concrete, but what should I use as a vapor barrier on the framing above the foundation?

If I continue the fb in the new wall to the ceiling, do I use 6 mil on the warm side of fb on the top half of the new wall then tuck it behind the EPS where it meets the foundation? Doesn't seem right working the 6mil around all the studs, lots of holes.

Or...do I insulate only within the existing framing on top of the foundation, put 6 mil on the warm side of that, and tuck into the EPS where it meets the foundation? This would leave air gaps between studs of the new wall and behind, also doesn't seem right. I read somewhere air gaps in basement walls promote air flow increasing moisture movement and drafts, maybe that's called convection.

I'd like to stuff the entire cavity (created with the new framing above the pony wall) with fiberglass (or something else, suggestions?) but can't find a definitive answer on where to put the vapor barrier.

I live in Vancouver Canada, the house was built in 1962.

Thanks eh,

c.

Advertisement

hobbs in vanvouver is offline   Reply With Quote
Old 01-11-2011, 04:12 AM   #2
Member
 
Join Date: Dec 2010
Location: SW Ontario
Posts: 192
Rewards Points: 152
Default

vapor barrier on basement pony wall


I have the same scenario in my basement (Ontario house built in '66) and would like to bump this to the top for more views.

Is the framing on top of the pony wall an interior wall?

Advertisement

pete0403 is offline   Reply With Quote
Old 01-11-2011, 03:27 PM   #3
hobbsInVancouver
 
Join Date: May 2008
Posts: 10
Rewards Points: 10
Default

vapor barrier on basement pony wall


Hi Pete,

The framing on the pony wall is not an interior wall, it's 2x6 studs on the exterior rim of the foundation.

Not sure you'd need insulation or vapor barrier on an interior wall, guess that depends on what the other side of the wall is used for though...

So, far as I can tell, my best bet is a vapor retarder above the pony wall, such as kraft faced insulation. No 6 mil at all. Rigid board against the foundation, well sealed, then faced fiberglass batting in the existing framing above, (paper facing warm side of fb). I'll pack the new framing with fb as well without a barrier so any vapor that gets in can dry to the exterior or interior.

I found a lot of good info at http://www.buildingscience.com though I think this is a consulting firm that tests in labs, not the real world, for what it's worth. http://www.homeconstructionimprovement.com is good too.

Haven't started the job yet though, so if anyone has any feedback on my "kraft faced fb as vapor retarder" solution, be glad to hear it.

Cheers,

c.
hobbs in vanvouver is offline   Reply With Quote
Old 02-13-2011, 09:07 AM   #4
Newbie
 
Join Date: Feb 2011
Posts: 1
Rewards Points: 10
Default

vapor barrier on basement pony wall


Hobbs,

With respect to insulating your basement - or anything else for that matter, small gaps or penetrations and incompletely sealed transitions etc., in your vapor barrier create enormous problems by concentrating moisture movement through them. What you need is a single, monolithic barrier to moisture movement.

While it is more expensive, spray foam insulation, when properly applied is the very best solution - it creates a thermal barrier, an air barrier and a recognized vapor barrier in a single application. It has a higher R value than any other material on the market and because it locks out moisture, it will eliminate that slight damp and occasional musty smell that basements can sometimes take on.

There is a good local spray foam blog if you are interested in more on spray foam in the Fraser Valley and Vancouver.

Cheers!
Mark in YVR is offline   Reply With Quote
Reply


Thread Tools
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Advice on retaining wall replacement (pics inside) eastie Building & Construction 0 04-05-2010 11:32 AM
Leaking Basement Wall MStocks Building & Construction 3 10-29-2009 10:57 PM
bathroom shower in basement along foundation wall jeeper Building & Construction 1 04-16-2009 08:20 PM
Basement leaks in brick wall Nick General DIY Discussions 8 07-18-2006 05:29 PM
Basement wall Problem dazusa Building & Construction 2 01-20-2005 10:16 AM




Top of Page | View New Posts