Crawl space problem

[gmoore7]

Hi Massoud,

In Canada crawlspaces are required to have ground cover. If it is an unheated crawlspace it must be 10 mil poly (other materials are permitted though), joints lapped at least 4 inches and weighted down. If it is a heated the crawlspace the poly requires 12 in of lap.

I am fairly certain these requirements have been in place since 1975 so anything built after that should be installed in this manner. If the crawlspace is older than this requirement these are a definate recommendation of good building practice.

[James L. Keilson]

Originally Posted by badair

glad my mentors showed a bit more patience otherwise i’d still be on the nipple and in diapers
although the prior is still enjoyable
the latter may be in my future
htbh

back to the OPs ?
this may help guide and explain further

Great links Barry..

Jim

[Kenton H. Shepard, CMI]

Originally Posted by mmojbafan

Hello everyone...
One of my client wants cover the whole earth of his basement a plastic sheet (some kind of vapor barier).

I know that it will stop the humidity to rise however I think it also block the humidity to scape. I have seen many crawl spaces that actual water stays on the plastic and has no place to go...

Which method would be the best?

Thank you

He's in Canada. A plastic cover in the crawlspace is very common and is good. It helps reduce the amount of moisture entering the crawlspace from the soil. If it is sealed at the laps and edges it may reduce radon, if that is a problem at that home.
If you see water on top of the plastic there's a good chance that water is getting in from outside or there's a plumbing leak. You should look to find out where the water is coming from.
Keep asking questions on the message boards Massoud, that's how you learn. There are many people here who are happy to help those who want to learn.
If you post in the Canadian forum you may get help more specific for Canada, like post #16 from Gerald.