I am building a 250 gallon RF trailer unit. Yesterday my partner and builder got a "smoking" deal on some sheets of 3/16 steel plate. I want to use it to do a double wall with an insulater between the layers. Has anyone used sand as an insulater? I know it's not lite weight, but it's cheap, and I would think it would do well. Any comments?
Edited by Fourthwind - 8/23/10 at 8:36pm