How to install a new fireplace

Installing a fireplace in an existing opening is a straightforward job but for safety's sake, any work involving the chimney flue must be tackled by a professional.

Tools: Club hammer; bolster chisel; brick trowel.

Materials: Fibre cement board; 75 x 25mm planed timber boards; concrete, fireback; fire-proof rope; lime mortar; corrugated cardboard; brick rubble; fire cement; fireplace surround.

Installing a fireback
If you revealed an empty opening when you unblocked your fireplace and plan to use it for a solid fuel or coal-effect gas fire, you will need to install a fireback.

1. Measure the width of the opening. Firebacks are sold in standard widths of 400 and 450mm, but can be made in other sizes, if necessary.

2. Tap along the cutting line with a club hammer and bolster chisel to split the fireback in two.

3. Lay a bed of lime mortar where the fireback will sit. Position the fireback then move it forwards slightly and sandwich lengths of fire-proof rope between it and the edges of the fireplace opening.

4. Slot 2 lengths of corrugated cardboard the height of the fireback behind it, mortaring them in place. When you first use the fire this cardboard will burn and leave a crucial expansion gap to allow the fireback to expand in the heat.

5. Use the broken rubble created by opening up the fireplace and mortar to fill the space behind the fireback.

6. Once you have filled to the level of the lower section of the fireback, use mortar to fix the upper section in place. Remove any excess mortar from the joint and continue filling behind the fireback.

7. Finish the fireback with a sloped line of mortar around the top edge, chamfering the join with the rear face of the flue. This will encourage smoke to rise up the chimney.