If you're facing a chimney rebuild in Attleborough and want to know exactly what happens from the first inspection to the final clean-up, here is a clear account of how Thetford Roofers carries out the work.
Before any work is priced or planned, we need to see the stack properly. A ground-level look tells us something, but a close inspection from the roof or from scaffolding is what gives us a reliable picture of the stack's condition. We're looking at the mortar joints, the face of every brick course, the flaunching around the pot, and the lead flashings at the junction with the roof.
We check whether the stack is plumb - a lean of even a few centimetres indicates structural movement and tells us how far down we need to take the rebuild. We look for spalling brickwork, open joints, cracked or detached flaunching and lifting lead. We also check inside where possible - some stacks have collapsed internally above the flue gather, which changes what needs to be done.
If the chimney is redundant (the fireplace below is blocked off or the flue is not in use), we note that too, because it affects what we do with the pot and the flue at the top.
Once we've seen the stack close up, we give you a clear account of what the problem is and what we propose to do about it. We explain how far down the stack needs to come, what materials we'll use to match the existing brickwork, and what the flashing arrangement will look like once the job is done.
This is also the point where we'll flag anything else on the roof that needs attention while access is available - ridge tiles, slipped slates or tiles in the adjacent roof area, valley work near the stack. Combining any of that with the chimney rebuild makes sense, because the scaffolding cost is already absorbed in the main job.
We price the work before it starts. You know what you're paying before we lift a tool.
Chimney work requires proper access. A chimney rebuild is not a ladder job - the materials being handled are heavy, the working position needs to be stable, and the finished work needs to be carried out with both hands free. A scaffolding tower or roof scaffold is erected before demolition begins.
The scaffolding is positioned to give safe working access to the full height of the stack and to the roof surface immediately around it. On most terraced or semi-detached properties, this means a tube-and-fitting scaffold from the eaves level up, with a working platform at or just below the stack base. On detached properties with steeply pitched roofs, a full roof scaffold may be needed.
We make sure the scaffold is positioned so that fallen debris - and there will be debris when the stack comes down - can be controlled and cleared safely. Neighbours are usually unaffected, but we let you know if we'll need access to a neighbouring property or garden to erect the scaffold safely.
The existing stack is taken down course by course from the top. We work down to the first sound course of brickwork - usually to roof level or just below, though the exact point depends on where the masonry becomes genuinely stable and undamaged. Taking a stack down is careful work. Bricks come off individually, old mortar is cleaned from the remaining courses, and the debris is lowered in bags or a chute rather than thrown from the roof.
The lead flashings are removed during this process. If they are in good condition and the correct code of lead (typically Code 4 or Code 5), they may be reusable. In practice, once old lead is removed and the stack is rebuilt to a slightly different profile, cut-to-fit new lead usually gives a cleaner result. We'll tell you at the time what's worth keeping.
The flue liner, if present, is checked at this stage. Most residential chimney rebuilds do not require changes to the liner, but if the liner has cracked or collapsed, this is the time to address it - not after the stack is rebuilt and access is lost.
Rebuilding starts from the sound base course upward. New brickwork is laid in courses using mortar matched to the type of brick - lime-based or natural hydraulic lime for period brickwork, cement mortar for harder modern bricks. The mortar must be softer than the brick to allow slight movement without cracking the masonry.
Each course is checked for level and plumb as it goes up. A chimney stack that goes up slightly out of vertical at the base will be noticeably off by the time the top courses are laid. The bond pattern is maintained to match the existing stack below the rebuild point, so the junction between old and new is not visible from the ground.
Corbelling or any decorative detailing at the stack head is re-formed to match the original where possible. Where the original profile is unknown or the brickwork was plain, we build a clean, functional head that sheds water and looks right for the property.
Once the top course is laid and the mortar has had time to firm up, the flaunching is formed around the pot base. This is the mortar collar that holds the chimney pot and slopes outward to direct rain away from the stack head. It needs to be bonded firmly to the top brickwork course and must have a positive outward slope - a flat or inward-sloping flaunching collects water and cracks within a few seasons.
If the existing pot is cracked, misshapen or the wrong profile for the flue, we replace it at this stage. Fitting a new pot at rebuild time adds minimal cost compared to returning to the job later with a separate scaffold. Where the chimney is redundant, we fit a capped or ventilated pot to keep rain out while maintaining airflow through the flue.
The lead work is the last element to complete before the scaffold comes down, and it's the part of the job that most directly determines whether the chimney will leak. A well-rebuilt stack with poorly fitted flashings will still let in water. We take the flashing work seriously.
Step flashings are dressed up each side of the stack into chases cut into the fresh mortar joints. The back gutter or soaker arrangement behind the stack is formed to collect and direct any water that reaches the back of the stack away from the roof. The front apron is dressed down over the roof covering.
All the lead is properly dressed - pressed tight to the surfaces, not just laid on top. Chases are filled with fresh mortar after the lead is fitted. The lead is secured with clips or tucks at the appropriate intervals to prevent wind lift.
Before the scaffold comes down, we inspect the roof covering immediately around the stack. Any slipped slates or tiles disturbed during the work are reinstated. Ridge tiles at the top of the pitch are checked. If any additional work was agreed at the survey stage, it is completed now.
Any debris on the roof surface - broken mortar, old lead off-cuts, displaced tile fragments - is cleared before we descend. The scaffold is then struck and removed.
Once the scaffold is down, we clear the working area at ground level - mortar bags, packing material, old bricks and debris. We check the area around the property for anything that shouldn't be left behind.
From the ground, we do a final visual check of the rebuilt stack - checking it reads plumb, that the flaunching line looks even, and that the lead work is lying correctly at the roof junction. If anything looks wrong from ground level, we tell you before we leave.
If your chimney stack needs attention - whether you've noticed a lean, damp coming through, or just know it hasn't been looked at in years - call Thetford Roofers to arrange a survey. We cover Attleborough and the surrounding area from our base in Thetford, and we'll give you an honest assessment of what the stack actually needs before any work is agreed.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
