Hoping to get some ideas for durable, cold weather skirt

FrankShore wrote:
Hay bales work great, if you have access to them

Except for the mice it attracts.
If your wanting something temporary a roll of heavy duty visqueen, some 2x4s and a roll of duct tape. 90% of the deal is stopping or at least slowing the air movement under the RV. Adding a couple of drop lights and your underside should be toasty warm in all but the most extreme cold.