Originally Posted by TomGW As others have said, prices will depend on complexity and spec. The only thing I can answer: you do not need planning permission for internal works in your house, and that includes converting an integral garage to a habitable room*. However, you will require 'building control approval' for the structural works (removing walls) and the drainage for the new toilet/shower and if the building is 'listed' you will need listed building consent. *This assumes that your house was not originally ...