As long as the insulation doesn't sag within the walls, the insulation value should be the same once it dries. The bellypan insulation was originally stapled to the underside of the floor. When it gets wet, and vermin move in, it falls to the bottom of the bellypan. It's not doing much at that point, wet or dry.
We use a "Sealtech 430R" to find skin leaks. It is a large squirrel cage fan that sits on the floor inside the trailer. It has a large diameter flexible duct connecting it to one of the ceiling vents. It draws in large volumes of air into the trailer & exerts a small positive pressure inside the trailer. All windows & doors are closed during the test. We spray a soapy solution all over the exterior skin, including every rivet. As the testing goes on you check for bubbles forming around joints etc & mark for caulking after the trailer is washed off & dry. It's really amazing what you will find. The bottom line is, "they all leak" & anyone saying their's dosen't, is fooling themselves. The key is keeping a vigil for any signs of water & take action as soon as you see dampness. If you let it go, your floor will rot out, regardless of how new the trailer is. We are doing major floor replacement jobs everyday, which often include serious frame welding & fabrication.
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