https://articlescad.com/using-....upvc-cat-flap-door-p
Consider installing a cat flap onto the door made of upvc for those who want to allow your pet to leave and enter the house without fearing that they'll leave behind unwanted "gifts". This is cheaper than replacing the whole door and is simpler to install. It is possible to install an animal flap on your own uPVC doors, but it is a tricky job that could result in costly mistakes. Easy to install If you have a cat or dog in your home it is essential to allow them into and out of your home. This will ensure their safety,