Quick Answer
Unused chimneys can deteriorate differently from active ones, particularly when it comes to moisture and ventilation.
Active chimneys need sound brickwork and pointing to help prevent smoke escaping and rainwater entering. Unused chimneys also require maintenance, but adequate ventilation is especially important to prevent excess moisture becoming trapped inside.
Fitting an air brick directly into the chimney can help improve airflow and allow moisture to escape.
At Mendip Roofing Contractors, we recommend keeping the pointing, flaunching and brickwork in good condition, whether your chimney is regularly used or not. We can also fit air bricks to ventilate unused chimneys as part of our chimney repairs.
Why chimney maintenance matters even when your fireplace isn't in use
It’s easy to assume that a chimney which isn’t being used won’t need much attention. After all, if there’s no fire burning beneath it, what could go wrong?
However, unused chimneys still need maintenance, and there are some important differences in how they should be looked after compared with chimneys that are regularly used.
At Mendip Roofing Contractors, we help homeowners maintain both active and unused chimneys, making sure the brickwork, pointing and flaunching are in good condition.
Do active chimneys need different maintenance?
If you’re regularly using your fireplace or stove, it’s particularly important that the chimney’s brickwork and mortar joints are properly maintained.
The pointing between the bricks needs to be sound to help prevent smoke escaping through gaps in the chimney structure. It also helps stop rainwater getting into the brickwork.
Loose or deteriorating mortar can leave the chimney vulnerable to problems, whether it’s being used or not.
Our founder & director explains:
“If you’re using the chimney, you need to make sure all the brickwork is properly pointed so smoke can’t escape and water can’t get in. But any chimney should be kept in good order.”
Chimney Maintenance Checklist
Check the key maintenance considerations for your chimney.
General guidance only. A tick does not confirm that a chimney is safe to use. Have active flues and appliances checked by an appropriately qualified professional.
Why do unused chimneys need ventilation?
One of the main differences with an unused chimney is the need to consider ventilation.
Even when a chimney is no longer connected to a working fireplace, moisture can still build up inside it.
Without adequate airflow, that excess moisture may remain trapped within the chimney rather than being able to escape.
Fitting an air brick can help an unused chimney breathe, allowing ventilation through the structure and helping excess moisture escape.
This is something we can help with at Mendip Roofing Contractors.
Where is an air brick fitted in an unused chimney?
An air brick is fitted directly into the chimney’s brickwork.
Rather than installing it in the surrounding roof, the work involves removing a suitable brick from the chimney itself and replacing it with a ventilated air brick.
This creates an opening for airflow, helping the unused chimney release excess moisture.
The appropriate position and ventilation arrangement will depend on the chimney, so it’s important to have it assessed before making alterations & wider chimney repairs.
Do unused chimneys still need pointing and flaunching?
Yes. Whether a chimney is used regularly or hasn’t been used for years, the external brickwork still needs to be maintained.
Two important areas are:
Pointing: The mortar joints between the chimney bricks should be kept in good condition to help prevent water getting in.
Flaunching: The mortar around the chimney pots at the top of the stack should also be maintained.
Neglecting these areas can allow the chimney to deteriorate, regardless of whether there’s an active fire below.
An unused chimney isn’t necessarily a maintenance-free chimney.
Keeping active and unused chimneys in good condition
The biggest difference between maintaining active and unused chimneys is that an active chimney needs sound brickwork and pointing to help contain smoke, while an unused chimney also needs suitable ventilation to manage moisture.
However, both require properly maintained pointing, flaunching and external brickwork.
At Mendip Roofing Contractors, we carry out chimney repairs and maintenance, including fitting air bricks to help ventilate unused chimneys.
If you’re concerned about an unused chimney or want to make sure your existing chimney is properly maintained, contact Mendip Roofing Contractors to discuss the right approach for your property.