Removing a Chimney Breast

What is a chimney breast?

A chimney breast is the brickwork which encases the chimney as it rises through a property. Usually the chimney breast is inside the property and takes up space within rooms.

With semi-detached and terrace properties, chimney breasts are often built ‘back to back’ between individual properties – where this is so, 4 fireplaces in property will appear as 2 rows of 4 chimney pots on the chimney stack which will be shared by adjoining properties.

Why do people remove Chimney Breasts ?

Chimney Breasts are often removed by property owners when fires are no longer used to give increased living space. Older properties were built with fireplaces in every room - with modern central heating, chimney breast are often unused and considered as wasted floor space.

What problems are involved when removing Chimney Breasts ?

The main problem is that a chimney breast forms part of the structure of a house and carefully considered needs to be taken before starting work to remove it. Unless the whole chimney, from the fireplace to the roof stack is going to be removed, suitable support beams will need to be incorporated to support any masonry above to avoid structural distress or damage or even the collapse of the building. Special attention needs to be used where the chimney breast is on a party wall with a neighbouring property or where the chimney breast of an upper floor is going to be removed while leaving a working fire in the room below – in the latter case, partial removal is possible but a smaller chimney breast for the fire below must be left in place.

Once a chimney breast has been removed, there will be the need to make good the floor where the chimney breast once was.

How should one approach removing a Chimney Breast ?

The services of a Structural Engineer are almost essential to ensure the safe removal of a chimney breast – this will involve the engineer in coming up with a method of work, establishing if any supports are required and, if so, specifying them. The method of work and all designs will need to be submitted to the local building control office for approval prior to any work commencing. Where the chimney breast is on a party wall, the Party Wall Act also comes into play and your neighbour will also need to involved and approve before work commences.

Once the Engineers proposal has been approved, all work should be carried out to the approved designs, and the local building control officer invited to inspect the work carried out. The Building Control Office will, upon satisfactory completion of the work, issue a completion certificate should be kept with the deeds/Land Registry documents for the property so that it is available for any re-mortgage or sale.

The Rules and Regulations to follow

There are 5 main requirements to consider before carrying out the work:

  1. Planning Permission - unless the property is Listed or in a Conservation Area, Planning Approval is unlikely to be required, but it’s always worth asking the question.
  2. Building Regulations compliance to ensure:
    • Structural strength
    • Fire safety
    • Sound insulation
    • Maintenance of any neighbour’s chimney
    • Damp prevention
    • Ventilation to rooms
  3. Party Wall implications under the Party Wall Act - In England and Wales, when removing a chimney breast from a party wall, the written consent of the owners of the neighbouring property must be obtained before work is started (the Party Wall Act – it’s worth taking the advice of a surveyor with experience of this Act).
  4. Landlords Licence, if a leasehold property.
  5. The safety of any gas appliance that uses a party walls flue in neighbours or own property - consulate a Gas Safe Engineer, and get something in writing.  

If the chimney stack is to be removed to below the roof, the roof timbers will need to be extended to fill the gap, and matching roof covering used to fill the gap.

If the chimney stack is to be left in place and only part of the chimney breast below is to be removed, the brickwork above must be supported with a Rolled Steel Joist (RSJ) or other suitable support. What will be required will depend upon the size of masonry above and the adjoining walls which will need to bear the load.

If any unused chimney breast is retained, it will need to be ventilated at both the top and bottom. Any moisture in an unventilated wall or chimney will interact with the soot remaining in the used chimney and can cause staining.