accoustic; soundproofing; ceiling

I intend to soundproof a ceiling in a Victorian property (built aporox 1860). I will be: 1. Taking down lath and plaster ceiling (done and horrible job) 2. Use accoustic sealant on areas where there is a hole in the floorboards (above), for example radiator pipes. 3. Using RW3 Acoustic Slab...