Chimney stacks are among the most exposed parts of a property. Rain, frost, strong winds and changing temperatures can gradually cause mortar joints, bricks, leadwork and flaunching to deteriorate. Identifying problems early can help prevent relatively minor defects from developing into more extensive and expensive repairs.
Chimney Repair Specialists Near You
Chimney repairs can involve several different parts of the chimney and surrounding roof. Before recommending work, a professional should inspect the condition of the chimney stack, brickwork, mortar joints, chimney pots, flaunching, lead flashing and adjoining roof covering.
Common chimney repair services include:
Chimney repointing
Leaking chimney repairs
Lead flashing repairs and replacement
Chimney flaunching repairs
Chimney pot replacement
Chimney cowl installation
Damaged brick replacement
Chimney stack rebuilding
Chimney rendering repairs
Lead back gutter repairs
Storm-damaged chimney repairs
Roof repairs around chimney stacks
Through iProTrades, you can describe the problem with your chimney and compare quotes from local tradespeople experienced in chimney and roofing work.
Leaking Chimney Repairs
Water appearing around a chimney breast or on a ceiling close to a chimney can have several possible causes.
A leaking chimney may be caused by deteriorated mortar joints, damaged brickwork, cracked flaunching or defective lead flashing. Problems with roof tiles, slates, soakers or the chimney back gutter can also allow water into the property.
Water can travel through the roof or chimney structure before becoming visible internally, meaning the location of a damp patch does not always identify the source of the leak.
A roofing specialist should therefore inspect the complete chimney and surrounding roof before recommending repairs.
Chimney Repointing
Mortar joints between chimney bricks naturally deteriorate over time. Chimneys can be particularly vulnerable because they are exposed to weather from several directions.
Cracked, loose or missing mortar can allow additional moisture into the masonry and may eventually contribute to loose brickwork and further deterioration.
Chimney repointing involves carefully removing deteriorated mortar from the joints and replacing it with suitable new mortar.
Where the existing bricks and chimney structure remain sound, professional repointing can help restore the weather resistance of the chimney and extend the life of the existing stack.
Chimney Lead Flashing Repairs
Lead flashing creates a weather-resistant junction between a chimney and the surrounding roof.
Depending on the position and construction of the chimney, the leadwork may include step flashing, cover flashing, soakers and a back gutter.
Over time, lead can split, lift or become detached from the masonry. Incorrectly installed or previously repaired flashing can also be a common source of chimney leaks.
A roofing specialist can inspect the existing leadwork and determine whether a local repair is appropriate or whether sections of flashing need replacing.
Chimney Flaunching Repairs
Flaunching is the mortar or concrete surrounding the base of chimney pots at the top of the chimney stack.
It helps secure the chimney pots while creating a surface that allows rainwater to run away from the top of the chimney.
Because flaunching is highly exposed, years of rain, frost and temperature changes can cause it to crack or deteriorate.
Damaged flaunching can allow moisture into the chimney structure and may eventually affect the stability of the chimney pots.
Depending on its condition, local repairs may be possible or the deteriorated flaunching may need to be removed and renewed.
Damaged Chimney Brickwork
Chimney bricks can deteriorate after prolonged exposure to moisture and frost.
Water absorbed into porous masonry can freeze during cold weather. As it expands, repeated freeze-and-thaw cycles can eventually damage the surface of the bricks. This deterioration is commonly known as spalling.
Individual damaged bricks can often be carefully removed and replaced without rebuilding the entire chimney.
Where deterioration is widespread, however, partial rebuilding of the chimney stack may be required.
The condition of the mortar joints should also be checked because deteriorated pointing can allow further moisture into the masonry.
Chimney Pots, Cowls and Caps
Chimney pots can become cracked, loose or damaged through age, weather exposure and movement within the chimney.
A loose chimney pot should be investigated promptly because it could become dangerous, particularly during high winds.
Depending on its condition, an existing pot may be secured when the surrounding flaunching is renewed or may require replacement.
Different types of chimney cowls and terminals are also available. They can be used for purposes such as helping prevent birds and debris entering the chimney or reducing direct rain entry.
The correct solution depends on whether the chimney is active or redundant and, where applicable, the fireplace or appliance connected to the flue.
Chimney Back Gutter Repairs
Where a chimney passes through a pitched roof, rainwater travelling down the roof needs to be directed safely around the chimney stack.
On the upslope side of many chimneys, a back gutter is used to collect and divert this water.
Damaged, blocked or incorrectly installed back gutters can be a source of water ingress around a chimney.
Repairs may involve renewing leadwork, improving the existing detailing or replacing damaged tiles or slates around the chimney.
Chimney Stack Rebuilding
Not every damaged chimney needs rebuilding. However, extensive deterioration, significant movement or unstable masonry can sometimes make partial or complete reconstruction necessary.
A chimney specialist should assess how much of the existing structure can safely remain and explain why rebuilding is recommended.
Where appropriate, replacement bricks and mortar should be selected to complement the existing building, particularly on older and traditionally constructed properties.
Chimney Rendering Repairs
Some chimney stacks have a rendered finish rather than exposed brickwork.
Over time, render can crack, become loose or separate from the underlying masonry. Once this happens, water may penetrate behind the surface and contribute to further deterioration.
Small areas may sometimes be repairable, while extensively damaged render may need to be removed before the underlying chimney is inspected and prepared for a new finish.
Simply covering damaged render without investigating the cause may conceal rather than solve the underlying problem.
Chimney Repairs on Slate and Tiled Roofs
Repairing a chimney frequently involves work to the surrounding roof as well as the chimney itself.
Tiles or slates may need to be carefully removed to access lead flashing, soakers or other weatherproofing details.
Any damaged roof coverings should then be replaced and the surrounding roof correctly reinstated.
For this reason, a contractor experienced in both roofing and chimney repairs can be particularly useful when water ingress is occurring around the junction between the chimney and roof.
Storm-Damaged Chimneys
Strong winds and severe weather can expose existing weaknesses within a chimney.
Loose chimney pots, deteriorated mortar and damaged masonry can become particularly hazardous if sections of the chimney become unstable.
Signs of storm damage can include fallen mortar or bricks, displaced chimney pots, damaged flashing or visible movement within the stack.
If you suspect that a chimney has become unstable, avoid attempting to access the roof yourself. A suitable professional should inspect the chimney and determine whether temporary safety measures or urgent repairs are required.
Signs Your Chimney May Need Repairing
Some chimney defects can be difficult to see from ground level, but there are several warning signs worth investigating:
Water stains around the chimney breast
Damp patches on ceilings or walls
Cracked or missing mortar
Loose chimney bricks
Spalling or damaged brickwork
Cracked flaunching
Loose or damaged chimney pots
Lifted or deteriorated lead flashing
Pieces of mortar or masonry appearing on the roof or ground
Persistent leaks during heavy rainfall
Visible leaning or movement within the chimney stack
Early investigation can help prevent minor defects from developing into more substantial damage.
Repair or Rebuild a Chimney?
Whether a chimney should be repaired or rebuilt depends on its age, construction and the extent of the deterioration.
A chimney with sound brickwork but deteriorated mortar joints may only require repointing. Individual damaged bricks, defective leadwork or cracked flaunching can also often be repaired separately.
Where deterioration affects a substantial proportion of the stack or there are concerns about stability, partial or complete rebuilding may be more appropriate.
Before agreeing to major work, ask the contractor to explain what has failed, what can be retained and why the proposed repair is necessary.
Choosing a Chimney Repair Specialist
When comparing chimney repair quotes, price should not be the only consideration.
Make sure the contractor has properly inspected the problem and that the quotation clearly explains the proposed work.
Depending on the project, a detailed quotation may cover:
Access and scaffolding
Chimney repointing
Replacement bricks
Lead flashing and soakers
Lead back gutters
Flaunching repairs
Chimney pot replacement
Cowls or terminals
Roof tile or slate repairs
Waste removal
Guarantees where applicable
Because chimney work normally takes place at height, suitable access and safe working arrangements are also important considerations.
Find Chimney Repair Specialists Near You
Whether you have a leaking chimney, deteriorated pointing, damaged lead flashing, cracked flaunching or a chimney requiring more extensive restoration, iProTrades can help you find local tradespeople for the job.
When submitting your project, provide as much information as possible about the problem. Photographs taken safely from ground level, a window or an existing roof survey can also help tradespeople understand the work required.
With iProTrades, you can compare up to 3 quotes from local tradespeople before deciding who you would like to carry out your chimney repairs.