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 03-21-2009, 07:26 PM   #1
Member
 
Join Date: Nov 2008
Location: California
Posts: 347
Share |
Default

Vapor barrier for shallow crawl space?


My house has a narrow crawl space (mostly about 1 foot deep or so, and about 3 feet deep at the max). There is no easy access to the area---to really get at it would require taking up a lot of the subfloor, which would not be fun (I know, since I had to remove subfloor when remodeling my bathroom). There was a small narrow opening at one edge of crawl space, but I sealed that (with sheet metal) to keep the rodents out.

Winter is very humid in this area (1600' elevation, 12 miles from the ocean, most of the winter it's raining and/or were covered by a fog bank). I'm concerned that the moisture under the house is going to lead to dry rot, so I'd like to have a vapor barrier underneath. However, it would be virtually impossible to get a plastic sheet down. Is there any alternative, other than a dehumidifier? We've got the most expensive electricity in the country, so that option could get costly. Thanks.

Jeremy Hillary Boob, PhD is offline   Reply With Quote
Old 03-21-2009, 07:38 PM   #2
Don't know it all, yet!
 
Join Date: Jun 2008
Location: Metro Atlanta, GA
Posts: 910
Default

Vapor barrier for shallow crawl space?


Other than the humidity and close to the ocean, please tell us where you are. Florida, Maine, Washington,? Ventilation seems the best remedy, but maybe not in northern climates.

__________________
If it's worth doing, it's worth doing right. If you wouldn't put your name on it, it ain't done right!
downunder is offline   Reply With Quote
Old 03-21-2009, 07:39 PM   #3
Member
 
Join Date: Jan 2009
Location: Long Island
Posts: 348
Default

Vapor barrier for shallow crawl space?


so you want a vapor barrier but you dont want to pull up the sub floor or use any type of electric and theres only a foot of space?


Im gonna watch this thread.
II Weeks is offline   Reply With Quote
Old 03-22-2009, 09:23 AM   #4
Member
 
Join Date: Nov 2008
Location: California
Posts: 347
Default

Vapor barrier for shallow crawl space?


Quote:
Originally Posted by II Weeks View Post
so you want a vapor barrier but you dont want to pull up the sub floor or use any type of electric and theres only a foot of space?


Im gonna watch this thread.
Yes, that's basically it. If pulling up the subfloor is the only solution, then I might be willing to do it, but that would be a last resort.

In response to another poster: I'm located in Northern California. Here, the winter temps are commonly in the 40s, and occasionally in the 30s (we get light snow a couple times/year). In winter, it usually rains a lot---like every day for months on end---and is often foggy. The remainder of the year it never rains and there is seldom fog.

The crawl space could be ventilated, I suppose, but using outside air would be pointless, since it would be just as humid as the air in the (sealed) space, if not more so. Also, we heat entirely with a pellet stove, and our inside temp varies from the upper 40s (winter nights), to the 70s or higher, and during the rare summer heat wave, it can get into the 90s. So, ventilating the crawl space with inside air does not seem like a viable option either...
Jeremy Hillary Boob, PhD is offline   Reply With Quote
Old 03-22-2009, 06:53 PM   #5
Member
 
Join Date: Mar 2009
Location: South Caroling
Posts: 59
Default

Vapor barrier for shallow crawl space?


If you seal the crawl completely then you will have your dry rot, the worry is if there is sitting water in the crawl, that will lead to mold or mildew. Dont seal the crawl completely, take your piece of metal off and pre cut some plastic bite the bullet and crawl in there. You can make several cuts in the plastic in order for it to fit in the crawl, just overlap the cut areas. Have a friend outside with cut pieces for you.
Toolmaster is offline   Reply With Quote
Old 03-22-2009, 07:42 PM   #6
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Default

Vapor barrier for shallow crawl space?


The vapor barrier should go up the foundation walls and stapled to the rim joist. While in there, be sure to seal the rim joist with foam insulation and rigid foam on the walls. Tape any cuts on the plastic if you need to use smaller pieces. Overlap these seams by at least 6" I would do 24" overlap.
Bob Mariani is offline   Reply With Quote
Old 03-23-2009, 10:20 AM   #7
Member
 
Join Date: Nov 2008
Location: California
Posts: 347
Default

Vapor barrier for shallow crawl space?


Quote:
Originally Posted by Toolmaster View Post
If you seal the crawl completely then you will have your dry rot, the worry is if there is sitting water in the crawl, that will lead to mold or mildew. Dont seal the crawl completely, take your piece of metal off and pre cut some plastic bite the bullet and crawl in there. You can make several cuts in the plastic in order for it to fit in the crawl, just overlap the cut areas. Have a friend outside with cut pieces for you.
It would be physically impossible to "crawl in there" for any sized human being. The space is just a few inches in a lot of places, maybe 1 foot on average, but a lot less at the entrance. So getting in there is simply not an option. The question is, given this limitation, what is the best way to go. Thanks.
Jeremy Hillary Boob, PhD is offline   Reply With Quote
Old 03-23-2009, 08:05 PM   #8
Member
 
Join Date: Jan 2009
Location: Long Island
Posts: 348
Default

Vapor barrier for shallow crawl space?


if its that important, really THAT IMPORTANT, than pull up the subfloor and start over then we can talk options
II Weeks is offline   Reply With Quote
Old 03-24-2009, 10:03 AM   #9
Member
 
Join Date: Nov 2008
Location: California
Posts: 347
Default

Vapor barrier for shallow crawl space?


Quote:
Originally Posted by II Weeks View Post
if its that important, really THAT IMPORTANT, than pull up the subfloor and start over then we can talk options
I don't know if it is really that important. Any opinions?

Jeremy Hillary Boob, PhD 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
crawl space and moisture Jeremy Hillary Boob, PhD Building & Construction 5 11-27-2008 08:13 PM
thoughts on crawl space heating rtoni HVAC 3 09-30-2008 12:47 PM
Inadequate center support in tight crawl space 4just1don Building & Construction 5 09-28-2008 03:29 PM
crawl space confusion shoestring General DIY Discussions 1 07-27-2008 01:06 PM
Crawl Space In Basement -- Please Help thekid Building & Construction 7 01-04-2008 08:15 PM




Top of Page | View New Posts

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