I have 1 month left for the "Conversion of garage into habitable room. Removal of existing garage door and installation of new door to match existing, with openable window and escape hatch". I don't want to do the interior work of adding a staircase to connect the garage to our flat above at the present time as we currently have good tenants in place, so this will be done in the future BUT I need to "start" the work so that Planning Permission is not lost. Conversion of the garage into a habitable space has sort-of happened as it's full of furniture (!) however I'm aware this doesn't mean work has started. If I purchase new garage doors and temporarily fit them over the current doors until we start work proper would that constitute starting the works? Or what actually would constitute a start?