Active job

Tiling over brickwork

I am seeking a tiler to tile over existing fire brickwork in a kitchen alcove (can provide photo) where we are planning to install a free standing wood burner.   The area requiring tiling is approximately 2.32 sqm on the floor and 6.46 sqm for the walls, ceiling and face of the alcove (not including the chimney outlet hole). The tiles we intend on using are from Tile Warehouse as follows: Wall, face and ceiling tiles - Chicago Bricks, State Street 200mm x 100mm and Floor tiles - Galaxy, charcoal 600mm x 600mm. in the bottom right corner of the alcove the tiles have been removed leaving a unlevel depression which would need to be evened out.   In addition, the walls of the alcove are rough fire brick which have had the old porcelain tiles chipped off. As the underlying surface is uneven, I am uncertain whether it would be more economical for us to install fireproof gib to provide a flat surface for attaching the wall tiles, or alternatively by having the tiler applying a layer of thinset directly on the brick.