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It is best to employ an professional to install a cat-flap inside your home. DIY jobs usually result in a poorly-fitted pet flap, which can let in drafts and cause more energy costs. SheffLOCK is able to install cat flaps on all kinds of doors, including wood, uPVC composite, glass and even external walls. On average, it takes about two hours to install the cat flap. Cost of pet flap A pet flap permits your cat to move around whenever it wishes. However, if the flap is not correctly installed, it may allow heat escape from your home and let other an