I have recently purchased a reclaimed 1960's ish tiled fireplace surround. It is in two main sections, a hearth and the surround with mantel. Both sections are based on concrete with the tiles fixed in. While the upright section has clear fixings to tie into the walls I have no idea how to fix down the hearth that it sits on. Do I simply sit it on the floor? Use some sort of tile adhesive? Do I mix a concrete or mortar base to bed it onto? Do I need to excavate some sort of footing? I am planning on using it as part of a solid fuel fire. I would really appreciate any suggestions or advice anyone can offer. Thanks.