I am in the process of dismantling almost everything, the interior is gutted, the floor in the bath, steps/door area, and forward under gaucho are to be replaced. All new systems, plumbing with pex, flex duct for heat, some new cabinetry, etc... So since I have it torn apart, my goal is to reduce weight wherever I can as I put her back together yet still be safe, functional and enjoyable. As far as protection from the cold I could put polystyrene below and along side like the black tank. My wife and I do not plan to be in any extreme temperatures, although I know cold weather can sneak up on you. Thank you for the feedback so far, any more?