Mike Paulsen wrote:


I tried that. A large name brand door was ~$80.00 and lasted ~6
months. The seal only worked when it was relatively warm and calm.
Replacement flaps weren't stocked locally and the frame was starting
to wear out. It might have faired better if I didn't have labs
charging through it dozens of times a day. I'm sure they make more
expensive doors which function better, but that gets too pricey.

Saw a Far Side cartoon with that very scenario. Large dog, tongue hanging
out, running full speed for the doggie-door. Inside, the door was barricaded
shut with a 2x4. In the corner was a cat, paws over its mouth to keep from
laughing out loud.