Rez temp much easier to control if you put it on a sheet of foam board in addition Weedhounds advice. If room temps are that low you have to get a heat scource and the space size will determine the best scource. I once saw a guy who did a grow in an un-attatched garage in the winter by hanging a tarp in a circle around the plants, bout 8-9ft diam. All he used was all the above with a small ceramic heater.