We have a handheld infrared surface temperature thermometer. The other night, when it was in the 20's outside, I discovered that the floor near one of the bedroom slideouts was 36. That slideout has since been shut and heat loss, or perhaps more aptly, cold gain, was only measured at 50.
When we visit campgrounds there are often semi-permanent motorhomes or trailers on site. I have noticed that many of them have insulated panels over their windows. Now I understand! The windows are all single pane, and several have a slight gap where the window opens. Brrr!
Yesterday morning it was 6 just before I took the pups out at 6:00 AM. Brrrr! While we were out walking the temperatures quickly rose to 8. Whew! A veritable heat wave!
May I remind you that we are in Red Bay, AL. AL stands for Alabama, as in 'The south'. It isn't supposed to get that cold down here. Not for more than "once in a great while".