The house is about ten years old there is visible signs that the concrete floor is sinking as the ceramic tiles are cracking in some areas

First off you need to find out what type of floor it is and why it is sinking. Sometimes when a builder gets cheap they don't compact the dirt enough under a slab and it can sink by its shear weight ( settle ) more then other floors. Is the floor crooked? If you pour water on it ot set a marble down does it run to one side? Some slab foundations are tied into the other half of the foundation and that is important to know.

You may need to look into concrete jacking:

What is Slab Jacking - The Concrete Network (http://www.concretenetwork.com/concrete/slab_jacking/what_is_slab_jacking.htm)