https://lovewiki.faith/wiki/Ho....w_to_Install_a_UPVC_
https://morphomics.science/wik....i/Installing_a_upvc_
Double glazing can be fitted with dog and cat flaps to allow your pets to go and go whenever they want. They are also great for keeping an eye on your pet while you are away from home. It is possible to put the cat flap onto an existing uPVC panel or double glazing glass sealed unit, but you will need a replacement piece with a premade hole. This can be accomplished by a glazier who has the proper equipment and skills. Easy to install A cat