I’m attempting to retro-fit what amounts to an external wall around the studio yurt bathroom extension. I will fill the wall cavity with insulation. I hope this will reduce or eliminate the problem we are having with frozen water lines.
I’ve learned a lot, through trial and error… with an emphasis on error… about cold weather winterization. Bottom line: even too much insulation is not enough when the temperatures drop to single digits or below zero (that is, -12˙C or below, if you’re so inclined). The vacation rental yurt bathroom extension was not constructed to endure extended sub-freezing temperatures, and it was definitely not designed to withstand single-digit or sub-zero temperatures.
That’s what we get for hiring a handyman from Hawaii to build it for us.