iceQ, please dont waste ur money on the injection. it doesn't work. u only waste ur time and money and doesn't solve the problem. i should know, me and my upstairs neighbour tried it all before, doesn't work. it only pushes the leakage to another place, and pretty soon u will hv 2-3 place leaking. even worse!!

the only solution is, u ask contractor to come and hack ur tiles up, re-waterproof it, and then tile it back again. that's a permanent solution, and u dont have to worry about it anymore.

it only cost about rm1,500. plus materials, labour and tiles. Get a few contractors in (don't rely on management one only). It is a bit of hassle, but better u hassle now than hassle later.

good luck!