Active job

waterproof main bathroom #2

We noticed that when we moved into our house 7 years ago that water spray from the shower that landed on the tiled floor outside the shower tray would drip down into the dining room below. We solved that problem by just using a shower curtain and we've never had any more issues until we had children. And we've now had a instance where one of our children emptied a bucket of water over the floor and this has caused water damage to the laundry below and bathtime can get splashy!! We're not looking at renovating our bathroom as there is still good life in it but we would like to properly waterproof the bathroom to avoid any further damage by water being spilled onto the floor. I imagine that this would involve ripping up ( reusing hopefully) the tiles before putting down a waterproof membrane and putting the tiles back but we are open for any advice on the best way to achieve this.