I am renting in a fairly old house which has a leaky basement (which I hope to have alleviated somewhat by making sure the gutters are working properly, and will be getting a dehumidifier) that has an adjoining crawl space, which is dirt floored and opens into the basement. I am thinking of doing my best to deal with the moisture by vapor sealing the crawl space. Once I do that, can I close it off from the main part of the basement? Or should it remain open to let air flow? I haven't been into the crawl space yet to see if there are vents. Thanks, hope someone sees this and can offer some advice.