i have an fireplace opening at the top is the lintel , inside the fireplace is the flue which is bricked in i need to raise the height by about 500mm the width of the fireplace is 800mm , we also need to raise all the brick and the flue on the inside aswell as the lintel , is this brick on the inside structural or do think we can just chizel it out and advise would be gladly welcolm thank you
