We purchased a 31 foot travel trailer from out neighbors knowing that we needed to replace a lot of wet areas. The trailer had a distinctive odor to it and we know that it was from the wet insulation, wood, etc. because when we opened it up the odor was breathtaking. We replaced what needed to be replaced, sealed up any wood that still had some good structure to it. We still have a slight odor (very slight) that we just cant seem to find and it is driving us nuts. It actually seems to be worse at night . Sometimes I even wonder if it is coming from a ceiling vent?????? Surely not, but could there still be something damp that will never dry out that we are just not catching????? I few squirts with Febreeze helps tremendously but not permanently.