How to Install a Vapor Barrier in a Crawlspace ~~ This article will show you how to add 6 mil plastic sheeting on the ground and insulate the walls in your crawlspace. We use foil-faced rigid insulation to keep the space under the house dry. The plastic and the insulation will eliminate any moisture problems you have in the crawlspace, such as water droplets collecting on the concrete walls and pipes.
I've been reading a lot about unvented crawl spaces. Seems like it might be a good idea for the mobile home. Isn't this a sight to behold?! My dream trailer looks like this underneath. Rigid foam insulation up next to the skirt. Nice white vapor barrier. Insulation under the floor. Even a light fixture!. Will have to navigate and tape around all that blocking, too.