Sorry if this Q has been asked many times before but, i`m looking at fitting one and was wondering if the brickwork around it (which is an existing chimney but needs a bit of a face lift )needs to be a firebrick plus what is used to cover the hole above the stove. It`ll be fitted into an adequate gap so it won`t be to close to the walls. Also do I need to fit a liner all the way to the outside or is there just a short length that fits onto the top of the stove. Many thank