I am about to embark on a lengthy upgrading project in my crawlspace and one of the big items is installing a vapour barrier across the entire crawl space floor, as whomever built the house simply put a skimcoat over the ground. As a result, my place gets rather humid during the winter months.

At any rate, I am curious as to how far up I need to cover with the vapour barrier. Do I simply run it up to the tops of the footings & seal it there, or does it need to go up higher on the walls?

Will be using 10 mil poly down there to ensure a strong surface on the floor should I ever need to go down there and move around.