https://valetinowiki.racing/wi....ki/Using_uPVC_Cat_Fl
A cat flap that runs through the wall lets your pets come out and in as they please. But, you should be careful not to install it too high on the wall. This could result in energy loss and allow burglars to break into your home. A hole in a cavity can also be a problem for future owners should you decide to sell your house. Glass cat doors are a safer option. Easy to install A through wall cat flap is a great method to allow your cat to leave and come back as it pleases. It is easy to install, and there are several models