After careful consideration I have decided not to tile over my oak floor and instead rip it out down to the subfloor, and would like to install plywood and backer board for a new tile install. I have 3/4" subfloor and can only go an additional 3/4" more due to height problems. So here are my options to put over the 3/4" subfloor.
a) 3/4" plywood b) 1/2" plywood plus 1/4" backer c) 1/4" plywood plus 1/2" backer
Either choice would give me a combined floor of 1 1/2". So which would be best?