Went to look at a simple job, where the customer wants a number of recessed downlights installed in there bathroom replacing their existing fitting. They have bought their own 'B&Q special' fittings although they are not fire rated, and as i normally like to fit fire rated downlights i was after some advice. The building is an old cottage and the construction of it means there is no access directly above the bathroom ceiling. After cutting a number of holes into the ceiling for the run of my cables i can see i have a void of approx 150mm where the joists meet the plasterboard ceiling and the outside rooftiles. My question is can i get away with using the non fire rated fittings in this instance. Ive read on other threads if there is an occupied room above that fire rated downlights must be used i dont have that situation, but was wondering whether a void over a certain size must be covered aswell.