I have just purchased a large tin of Bitumen but not sure whether it is the right stuff to use for waterproofing the floor of my bathroom, it is made by Marley Waterproofing, there is nothing on the back to say you can use in bathrooms, it does say it protects the following Metal railings and gates, bases of wooden garden posts, drainpipes and drainage channels. i purchases from B&Q where the assistant said it would be fine, but i just want to make sure before i use it. If it is not the right one could someone please recommend which Bitumen i need and where i can get it from. many thanks