Cracked bathroom floor

[Mojo]

Just discovered 2 large wall-to-wall parallel cracks on our recently tiled bathroom floor. :cry: This is a new 2 storey extension - architect says NOW that we shouldn't have tiled - do they always crack? should we have been told that this was risky? what do we do about it now?

[plumbers1]

Did you use flexible two part good quality adhesive. Did you make sure floor material was fixed and no movement on floor sub structure and did you put down 12mm min WPB ply board. If you did these things you probably would not have a crack!!!