Same reasons. I musing backbeat for this rack, so I'm taping the flexwatt onto the back plate, and it stays a little cool in my apartment (76ish) so I'm using it to hold heat in as well. During the cooler months I'm going to add a door as well (not made out of melamine). I've heard some people having the room in the low 70s high 60s but with all sides enclosed it stays a nice 79-81 ambient temp in the tubs.