waterproofing dirt crawlspace


  #1  
Old 11-14-05, 08:13 AM
S
Member
Thread Starter
Join Date: Aug 2005
Location: Philadelphia area
Posts: 31
Upvotes: 0
Received 0 Upvotes on 0 Posts
Question waterproofing dirt crawlspace

Half of my small house is sitting on top of 20x10 crawl space about 3' high. There is never standing water in the crawlspace and things got a lot better after I installed gutters throughout the house, graded the soil and installed run-off pipes to the street.

Crawlspace has two small windows plus third window converted into the "entrance". There is currently no ventilation. It is perpetually moist and musty. Also, there is no underflooring insulation.

Plus, I have a borderline radon problem to content with: about 4.1. It would be nice to help that problem somewhat, but I certainly would not want to aggrevate the situation. Also, I have termites in the area ( I gutted and rebuild the house with numerous structural members replaced due to past termite infestation)

I was considering to install vapor barrier such as regular plastic or cross laminated polyethylene. Addtitionally I am thinking to put in automatic fan, such as:
http://www.rewci.com/crspve110cfm.html
in conjunction with vent for incoming air.

Any recommendations?
Where can I get plastic for vapor barrier?
 

Last edited by slvr00gt; 11-14-05 at 08:31 AM.
  #2  
Old 11-14-05, 09:05 AM
Join Date: Mar 2005
Location: USA
Posts: 5,650
Received 1 Upvote on 1 Post
waterproofing dirt crawlspace

Your most likely source of moisture is from the floor of the crawl space. Heavy plastic on the soil will do a good job. It is not necessary to get too fancy on the type, but make sure you don't puncture it. Lap and tap any seams.

You could tape it to the walls. This could make it more difficult for termite tubes (tunnels) to be form on the wall. - No guarantee, but it is cheap and could help.

After you do this you can take a look at ventilation.

Dick
 
  #3  
Old 11-14-05, 09:34 AM
S
Member
Thread Starter
Join Date: Aug 2005
Location: Philadelphia area
Posts: 31
Upvotes: 0
Received 0 Upvotes on 0 Posts
Originally Posted by Concretemasonry
Lap and tap any seams.
With regular ducttape?
 
  #4  
Old 11-16-05, 03:06 PM
T
Member
Join Date: Aug 2000
Location: USA
Posts: 15,047
Upvotes: 0
Received 2 Upvotes on 2 Posts
Duct tape will do fine to seal overlapped seams of plastic vapor retarder. 8 mil minimum or thicker will do. Lap it up the sides of crawl space and tape.

Termites? Call an exterminator to treat the soil with termiticide.
 
  #5  
Old 11-18-05, 11:16 AM
S
Member
Thread Starter
Join Date: Aug 2005
Location: Philadelphia area
Posts: 31
Upvotes: 0
Received 0 Upvotes on 0 Posts
Cool

Originally Posted by twelvepole
Duct tape will do fine to seal overlapped seams of plastic vapor retarder. 8 mil minimum or thicker will do. Lap it up the sides of crawl space and tape.

Termites? Call an exterminator to treat the soil with termiticide.


While all the the wall were out I put in spectracide termite powder in all wall cavities, then I also installed termite bait sticks in the house perimiter and in crawl space.

Online, I got termidor sc ( $80 for 12oz ) to treat the soil perimiter of the house, basement perimiter and crawl space

Will see how this multi-dimensional approach will work....

When I opened up the walls I had seen what the termites can do. Not pretty at all!
 
  #6  
Old 11-18-05, 11:33 AM
majakdragon's Avatar
Member
Join Date: Jul 2003
Location: N.E. Arkansas
Posts: 7,475
Upvotes: 0
Received 1 Upvote on 1 Post
Ventilating will be a big plus. I have many louvered vents for my crawlspace that I open in the summer and close in the winter. Next step is a fan. If you decide to insulate the floor, be sure the insulations vapor barrier goes up against the floor. (vapor barriers always go to the heated side). The idiot that built my house did it the opposite way and I had to tear it all out. Good luck.
 
 

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