Vapor barrier on hard dirt


  #1  
Old 02-25-15, 11:28 AM
S
Member
Thread Starter
Join Date: Sep 2013
Posts: 20
Received 0 Votes on 0 Posts
Vapor barrier on hard dirt

Hi, I was planning on using 12 mil plastic as a vapor barrier in my crawlspace. Upon closer inspection, a lot of the dirt down there is rock hard and somewhat jagged in places. Not a lot of room to move around so I don't think I could really break it up without having it take weeks. So instead I though maybe I will use a 20mil barrier instead. Would 20mil be sufficient or is there maybe something else I should do? thanks.
 
  #2  
Old 02-25-15, 11:32 AM
K
Member
Join Date: Apr 2014
Location: Nova Scotia
Posts: 750
Received 0 Votes on 0 Posts
Is your concern that the dirt in the crawl space will rip the vapour barrier? 12mil is pretty durable, and I can't imagine there being an issue with 20 mil unless you have some really sharp rocks sticking out of the floor.
 
  #3  
Old 02-25-15, 12:51 PM
S
Member
Thread Starter
Join Date: Sep 2013
Posts: 20
Received 0 Votes on 0 Posts
Yes tearing was my concern. I think I have only seen/felt 8mil plastic at the home depot, so was not sure how tough 12 was.
 
  #4  
Old 02-25-15, 12:58 PM
K
Member
Join Date: Apr 2014
Location: Nova Scotia
Posts: 750
Received 0 Votes on 0 Posts
It won't hurt anything to go heavier. It really depends on how much room you have to work, how sharp the surface is and how much care you are able to take when placeing it.
 
  #5  
Old 02-25-15, 02:53 PM
S
Member
Thread Starter
Join Date: Sep 2013
Posts: 20
Received 0 Votes on 0 Posts
Ok, I'll have to look at the prices and another look at my crawlspace floor. Thank you Keith.
 
  #6  
Old 02-25-15, 03:32 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Location: USA
Posts: 27,156
Received 933 Votes on 852 Posts
In addition to Keith's comments I would add that a lot of guys will lay carpet remnants down in high traffic areas, just to protect the plastic and it's easier on the knees. Contractors will often do this because they don't want to be the ones that rip the poly and then get blamed for it.

Hope you are rolling the poly up the walls and sealing all edges and seams with mastic.
 
  #7  
Old 02-25-15, 06:26 PM
S
Member
Thread Starter
Join Date: Sep 2013
Posts: 20
Received 0 Votes on 0 Posts
yes I am going up the walls and sealing it. It is my understanding that I would want to stop the poly at the top of the concrete footer and not cover any wood with it, so as to not trap moisture.
 
  #8  
Old 02-25-15, 06:31 PM
K
Member
Join Date: Apr 2014
Location: Nova Scotia
Posts: 750
Received 0 Votes on 0 Posts
Generally for below grade applications your vapour barrier would go up to the walls only to grade level to allow moisture to escape.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: