I read the recent condensation post with interest. So not to hijack that post about condensation, which has a good bit of in-season condensation defense suggestions, I thought I would start this one about off-season condensation issues. My TD is insulated, floor, ceiling and walls. When in use my ventilation fans change the cabin air either every four minutes or every two minutes depending on whether I have one fan or both running. I made sure to air it out after every trip even though I have never had condensation issues in use. I have a piece of indoor/outdoor carpeting over the floor (loose fit, not glued down). On top of that is a six inch memory foam mattress, wall to wall.
Should I be concerned about condensation during storage? The trailer is under cover with an occasional dusting of snow landing on horizontal surfaces. Weather extremes will likely be as cold as -20 degrees F; the average winter temp is probably in the 20s. I remember some folks mentioning that they prop their mattress up off the floor to provide air movement. That would be easy to do with a few pieces of 1 1/2" pvc pipe I have laying around. What do experienced cold climate TDers do to fight the condensation?