Does anybody out there have any idea if there will be a larger opening behind this fireplace - think it is called a builders opening? It’s a 1950’s house. I believe the fireplace was ‘modernised’ in the 70’s when the front decorative facade was added. I’d like to open it up and put a proper fireplace in and then use the open fire. Any thoughts  would be appreciated.

An 18” fireback will fit in but you can break out the brickwork surround and fit a 24” one I think , I like with fire clay throat pieces 

 

it would also be possible from the look of it to use it like it is - possible little repair low down at the back using fire cement after cleaning it up