Part P. Regulations 4 (2) states that, on completion of work, the building should be no worse in terms of the level of compliance with other applicable Parts of Schedule 1. These may include, but are not limited to, Parts B, E, F and J., For example, one or more perforations of a ceiling lining beneath a floor - made to accommodate recessed lighting or similar fittings - may have an adverse effect on that floors performance in terms of its resistance to fire and sound penetration. Due regard should therefore be paid to the guidance in Approved Document B (Fire Safety) on the performance of fire resisting and compartment floors, and Approved Document E (Resistance to the passage of sound).
All down lighters must be fitted by an installer that is registered by an approved Part P scheme or alternatively, this new electrical work must be notified to and inspected by your local Building Control Officer