Hi there, After having a leaking shower cubical due to previous owners/builders putting tiles straight onto plaster i have removed tiles to leave plaster which is drying as we speak. This is what i plan to do... 1. screw hardibacker 500 onto plaster using old studs behind (to remove old plasterboard unfortunatly is just not possible) 2. use WP1 tanking kit to waterproof (as sujested by members of this forum. 3 tile and grout I have done many searches on this forum and others and these are my unanswered questions...... 1. I have been told by a tile company selling hardibacker that i will not need to tank a shower cubical unless it was a wetroom how nessasary is this? (im using forum advice about tanking i had never heard of it before) 2. does the shower tanking kit include anything to fill the gaps between the hardibacker or do i use tile adesive? 3. do you tank onto the shower tray or is it just for the hardibacker? ie do i then seal the gap between the wall and tray with normal silicone? 4. due to existing walls the hardibacker will sit on the shower tray is this an issue? ie could a small leak at tray level soak up hardibacker and the old plaster behind act as a wick? 5. i understand that tanking is a latex if so does it set hard? do you just pop adesive striaght onto it and tile (after 24hours)? if so how thick? 6. any other top tips about corners/gaps etc? 7. what gap in mm do i leave between tray? im sure i will think of more questions as the job progresses many thanks for any help oh another one came to mind..... i was just going to tile down to tray and not use any of those plastic things wil that be ok?