the barn had heating, and the room where the reception dinner was held was actually quite warm. but part of the reception was held on like, this huge open-air deck and there was only temporary plastic sheeting for walls. (there was heat there, too, but it was only partially effective.)

i know the major reason for the venue was cost, the wedding party splurged on the open bar ;P

the hotel being like, 50°F with the 'heating' on was a lot worse, the barn at least got warmer as the wedding went on.