I purchased a newly constructed home in August of last year. When it rains, I have standing water in the crawl space sometimes for days at the time. I, too, have vents all around the house, plastic on the ground under the house, clean gutters, and plastic tubing connected to the downspoouts of the gutters. I haven't noticed any mustiness or "wet" smells yet, but my concern is the dampness getting into the walls of my house. Is this cause for concern?