I just want to mention this for anyone who might be interested. When I built my nest boxes I didn't put enough thought into the design, and as a result I had a hinge on the top that allowed rain and snow into the nest boxes. After we had a blizzard in November and my nest box was COMPLETELY FULL of snow, I decided I needed to try something. All stationary gaps I caulked with silicone, but I knew I needed something flexible for the nest box hinge. As a quick fix I decided to try some flex-seal tape, assuming it probably wouldn't last too long and I'd have to come up with a better solution eventually. Well, here we are almost 4 months later and it has really held up amazingly and remained flexible through snow, ice, rain, and sub-zero temperatures. It hasn't cracked, loosened, or shifted at all. The next test will be to see if it melts off this summer! So- while it's not the most polished look, it's a viable option for some coop issues!