In my opinion, if the wall is insulated you have no worries. The outside wall is where your floor is the strongest and can support the most weight. If the vinyl gets a little cold, I can't see why it would cause any issues in playback. First off when you take the record to your TT it will start re-acclimate to the ambient temp of the room. Which may be 2-6 degrees warmer or cooler depending on wall insulation R factor. After all the records were shipped in trucks that had no climate control, and they see, to play fine. That is my thoughts, other may dis agree, but that is the reason for the forum. You choose the logic you wish to adhere to.