Just thinkin.
you could also set them up some how with heat is your shop is cold. Get one of those alum surround work lamp, with squeeze clamp handle, put it about 1 1/2 feet off the ground.. in a corner, to at least to keep an eye on to where they will be.. Basically they follow the heat, unless it is really hot, they go to moist shady areas. hope this helps..
Snapshot_20141013.jpg
A pic of the lamp I was talkin about.. it act's like a heat lamp..