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Incorporating a cat flap into your bifold doors will provide numerous benefits for both you and your pet. It can also prevent extreme cold or hot weather from entering your home. The first step is to measure your pet's measurements to determine the size of the door flap you'll require. This will enable you to design an opening for your cat flap that is the right size. Outdoor Access Even those with no DIY skills can install a cat flap onto an external back door. This can help you avoid the expense and hassle