"Redneck" Yeti Cooler

I would think you would have some.  Several years ago we took out the curtains that covered the rear window in our 177.  It was replaced with a 2x cellular shade.  Two tests were taken when temps were in the mid 40's with the heater running. Furnace was set for 60 degrees at 7 pm with two people inside for the most part until 7 am the next day - so a 12 hour test.   With all windows shut and the cellular shade down there was still a fair amount of moisture build up between the shade and window, in fact we probably were able to decant nearly 2 oz. of water that sat in the two window channels.  Next night we opened two windows about 1/2" each on opposite sides of the bed that flanked the cellular shade.  Next morning there was still some moisture but not very much and the good news was there was no water in the two window channels at the bottom of the rear window.  So keeping some ventilation is critically important to keep things dry.  With two people breathing all night long, a fair amount of moisture is released.