https://squareblogs.net/oxband....2/back-door-with-cat
https://austin-collier-2.feder....atedjournals.com/upv
uPVC panels are a strong and long-lasting alternative to composite doors. They are strong, energy efficient, and fireproof. They are also cost-effective and easy to maintain. The easiest way to fit the cat flap onto a uPVC panel is to buy an additional double-glazed sealed unit that has a pre-made hole for the flap. This is a lot safer than cutting holes in an existing glass panel. UPVC Doors are easy to maintain Unlike traditional