There is not such thing as a "hardwood laminate" floor.

There are laminate floors, which are a picture of wood or tile laminated in plastic.

There are hardwood floors. And of those there are solid wood and enginneered wood.

The engineered floors are type of plywood with a hardware finished surface.

Laminate flooring and some enegineered wood flooring is installed as a FLOATING FLOOR. You can not install backerboard over a floating floor.

And a nailed or glued floor (solid or engineered floor) is not a good substrate for the backerboard.

You need to cut the finished flooring material back.

And what is the subfloor under the finished floor?

well under the finished floor I think is concreate.I dont want to rip up my house since it is only a year old.But where I want to do this is on the main level of the house.The flooring that is down is what you call a floating floor then. Three foot long tucked together pieces.

So I would have to measure and then cut out the part of floating floor then put in the hardy board then the slate?

Thank-you

Mrs.Billingsley

If the floor is concrete and it is "clean" then you just tile over the concrete.

You may need to use a wire brush to get it clean.

It should absorb water, if so the thinset will stick.