Interesting, he says, stroking his chin. That might be the solution if fatty puss keeps getting fatter, we do have a small internal room with a door. Mind you, she's pretty good at circumventing cat flaps, she has a knack of getting her claw into the gap and applying enough force to bend the flap so it pops over the catch. Or she'll just dig through the floor. Or deploy a small explosive device. She's proven to be an expensive cat, when we first got her, I left our office doors closed. One Saturday we came home to find she'd spent the day digging. The carpets didn't stand a chance and she was making good progress with the floorboards when we interrupted. Closed doors aren't generally a good thing. Mind you, last I heard, she was building a glider in the attic. Good luck flying with that belly.