https://www.openlearning.com/u..../vintherconnolly-sm4
https://byrne-kronborg.federat....edjournals.com/cat-f
A upvc-clad panel with a cat flap can minimize draughts in your home. By keeping your pets warm and cold air out you can save money on heating bills. While it is possible to install a cat flap into both upvc and double glazing sealed units, it can be more challenging than with doors made of timber. This is because upvc comes in different thicknesses. Benefits Having a cat flap fitted