https://algowiki.win/wiki/Post....:Back_Door_With_Cat_
Installing a cat-flap to your door is a simple procedure. You'll need to be aware of a few points before beginning. Upvc door panels that have a cat flap can be installed without needing to cut an opening in your door or wall. They are available from a variety of glass companies with a hole that is pre-drilled for the door for your pet. 1. Safety The cat flaps made from upvc can be easily erected and fitted to a variety of different doors. They are energy-efficient and weatherproof, and have draft-proofing built in to help i