Hi all , just quoting for some flat/apartments which will all be concrete ceilings with a 150mm MF ceiling , plaster boarded and skimmed . I’ve not done any for a few years so want to know what the minimum is now for fire containment? Is it acceptable to tie to MF rods with metal tyraps ? ( rough but got to be competetive on price ) or is tray a must ? Or could I make some loops out of all round band ? Just wondering what sparks use nowadays ? Cheers