A pro can do it in no time. If you are planning on a new hearth now is the time to do it. Most period fireplaces had a hearth that was flush with the floor and likely a replacement would sit on that so the fireplace would need to be raised an inch or so.

Wondered if you did anything with this, as only just seen it. The problem with that fireplace is that it has been installed on top of the hearth, the hearth too has been cut in to the skirting. Therefore, if you remove the hearth you will have a gap under the fireplace and would need to support it on the edges ( little bits of wood painted black? ) and you'd have gaps in your skirting. I would therefore, cut the hearth back flush with the fireplace and then carpet back to the skirting. I like period features and removing them is a bit sad. You can remove it in it's entirety and put in an air brick, that's fine without causing any problems involving building regs, but you'd still have the skirting issue.

rachelmidlands Massive belated thank you. HESmith had the very thing - couple of emails and the tiles were in the post to me. Brilliant.

Many 1930s fireplaces did have pretty ugly tiling. They were either built completely of tiles or the infill was tiled like yours. If it were mine I’d remove the tiles. I don’t like them either! I’m sure some people would say keep them so each to their own. They just don’t have the charm of Victorian or Arts & Crafts tiles.