I'm remodeling a very small bathroom (about 5'x7'). For now, I'll just be laying linoleum, but I would like to lay some concrete board so that I can at a later date tile the room. The flooring right now (under the existing linoleum) is a 1/2" thick plywood. It seems very solid and doesn't seem to buckle. This house was built some 40 years ago and the wood looks in excellent condition.
Anyway, how THIN of a layer of concrete board can I get away with? I don't want to raise the final level of the floor any more than necessary. Would 1/4" concrete be okay for a small job like this?
Thanks!