https://nerdgaming.science/wik....i/Cat_Flap_Fitters_N
uPVC door panels offer an alternative for composite doors. They are durable energy efficient and resistant to fire. They are also affordable and easy to maintain. A double-glazed sealed unit that has an opening already cut for the cat flap is the easiest method to install a cat flap in a uPVC sheet. This is much safer than trying to cut a hole in an existing glass panel. UPVC doors are easy to maintain Unlike traditional wooden doors, uPVC doors don't require frequent painting or sanding. They are also energy efficient and could