Fitting a mantelpiece over existing fireplace

Hi all

Newbie (and beginner decorator) here, so be nice

My query is this; I'm trying to spruce up my house, and currently have an old tiled fireplace from the 20's as my fireplace. It looks a bit like this;


...but without the hearth. I want to replace this with a new style wood mantelpiece and gas fire, which would look a little bit like this;


I've started by knocking the tiles off the old fireplace, which has revealed what seems to be concrete which was forming a basis for the tiles. Basically, what I'd like to know is; rather than knocking this down, is it possible to simply 'frame' the new mantelpiece over it and inset the new fireplace into the existing one? I know this probably sounds a bit vague, but just an idea of whether it's feasible or not would be great. Oh, and the fire has always been gas; until last week, we had an old gas fire mounted in front of this fireplace which I've disconnected, and the plan is for the new fire to also be gas.

Thanks in advance

I don't see why not. It would look great if you could get hold of some aged timber.

Oh, I'm not being that industrious. It's going to be a pre-fab job. Should that still be ok?

Yup. Can't see why not.