Here you can see a small knock through carried out in a hallway gaining access into an integrated garage. This is typical of the more common knock through as it enables the washing machine and various other utility items to be sited in the garage so that kitchen space is gained. In this case (see photos) the door was matched to the existing in the house, a Catnic lintel was calculated and secured and the opening was cut out. The walls were plastered in smooth, a door frame, architrave and then the door was fitted, ready for decoration. The typical cost.