Less than two weeks to go till our exploration trip to the Pacific Northwest and I am struggling to finish the soundproofing between the upstairs and downstairs of 23 Barton Road . I have been advised by building control that , in their view , as I had let out the upstairs and downstairs separately and locked the connecting door the property must comply with the building regs. for two flats. I have applied for planning to block off this door permanently and create two self contained flats even though the local planning officer tells me that having two flats ( a maisonette ) is unacceptable with my current layout as " the upstairs can overlook the downstairs garden " My professional planning advisor disagrees so we will see who is right - at my expense ! Anyway on to the Job . Here is the relevant British standard for flat separation First make sure existing ceiling is up to spec-I added a further layer of 15mm sound check plasterboard . Then fit a frame below and fi...