During recent investigation in roof voids above flats it has become apparent the roof void compartmentation does not mirror the flats and corridors below. Instead there are shared open roof voids covering 3 - 4 flats. This is a relatively new build and have been advised that this is accepted construction practice, assuming there is managed access to the roof void, detection in place and the ceilings are double boarded. I understand that new build housing schemes are now been constructed with completely open roof voids if the measures mentioned are in place. This does seem a bit conflicting with the guidance documents I have reviewed.
Any advice would be welcomed :)