We are in the process of moving house and our next property has no obvious door for a dog flap. Having had the convenience of one for the last 20 years, we (let alone our dogs!) couldn't contemplate NOT having one. The kitchen has plenty of outside walls which could have a dog flap put in to access the back garden but I'm not even sure if this can be done?! I assume it would be like a little tunnel? Would this be something that a builder would need to do? TIA