If you are facing a chimney rebuild in Necton, knowing exactly what the process involves - from the first inspection to the final clean-up - helps you plan properly and ask the right questions.
A chimney rebuild should never be quoted from the ground. What looks like a pointing job from the pavement can turn out to be a full structural rebuild once someone gets up close, and what looks alarming from below is sometimes salvageable with targeted repairs. The only way to know is to inspect the stack at close range.
That means access - either a scaffolding tower, a full scaffold run, or in some cases a roof ladder combined with a tower on the ridge. The access method depends on the roof pitch, the height of the stack and whether there are obstacles such as a conservatory or outbuilding below. On a straightforward two-storey property, a tower scaffold is usually sufficient. On taller or more complex buildings, a full scaffold is necessary to work safely.
During the inspection, a roofer is checking the condition of the bricks (are they spalling, hollow or intact?), the mortar joints (how deep has erosion gone?), the flaunching at the top (cracked, missing or sound?), the chimney pots (secure or moving?), and the lead flashing at the roofline (stepped in properly or lifting?). Each of these tells a different part of the story.
Once the scope of work is agreed, the scaffolding is erected. For most chimney rebuilds, this is a tower or a short scaffold run up one side of the house to give safe, stable working access to the stack. The scaffold must be solid enough to carry not just the roofer but also the materials - new bricks, mortar, lead - being lifted up to the working platform.
Planning for scaffold access matters practically for homeowners. The scaffold company will need clear access to the relevant side of the house, and a parked vehicle or locked gate can delay a start. It is worth clearing the area the evening before the scaffold is due to go up. The scaffold will typically stay in place for the duration of the rebuild work rather than being removed between visits.
For properties on terraced rows or with neighbouring buildings close by, the scaffold arrangement may need to account for the neighbour's side as well, and communication with neighbours before work starts avoids problems.
A chimney rebuild does not always mean taking the entire stack down to the roofline. The extent of the takedown depends on where the damage is and how far it has progressed.
If the damage is confined to the top section - spalling bricks above the roofline, failed flaunching and loose pots - the rebuild starts from where the sound brickwork ends, which is often a metre or so above the lead flashing. If the brickwork all the way down to the roof is compromised, the takedown goes to the flashing level. In extreme cases where the stack is unsafe even at the roofline, the work goes right down to the ceiling level of the top floor and what remains is assessed structurally.
Bricks and debris are lowered down by hand or in a bag, not thrown or dropped. This protects the roof covering and guttering below. Old lead flashing is carefully removed and the cuts in the brickwork where the lead was stepped are cleaned back ready for new lead to be dressed in. Any existing soakers - the small individual lead pieces at each course of tiles where the roof meets the chimney - are also removed and replaced as part of a proper rebuild.
New brickwork goes up course by course, with each bed joint fully filled and the perpend (vertical) joints tight. The mortar mix is chosen to suit the existing brickwork - lime-based for older soft bricks, sand and cement for newer stock. Using the wrong mix - particularly a mix that is stronger than the bricks themselves - causes cracking over time as the stack expands and contracts with temperature changes.
On older Norfolk properties, the brick type and bond (the pattern in which bricks are laid) is important for both appearance and strength. Flemish bond and English bond are both common on period stacks. A good roofer matches the existing bond where possible so the rebuild does not stand out.
Brick courses are kept level using a spirit level and line, not by eye. Any deviation in the early courses compounds as the stack rises, so accuracy at this stage determines whether the finished stack is plumb and upright. A stack that leans slightly after a rebuild is a sign the bricklaying was rushed.
Once the brickwork is up to the correct height, the lead flashing is fitted. This is the junction between the chimney and the roof slope, and it is one of the most water-sensitive details on the whole building. Getting it right requires cutting chases (slots) into the mortar joints of the brickwork at an angle, dressing the lead into those chases, and then pointing the chases with mortar to lock the lead in place.
There are two parts to a chimney flashing: the back gutter (behind the chimney, collecting water running down the roof slope), the side flashings (stepped up the slope on each side of the stack), and the front apron (at the front face of the stack, below the lowest row of tiles or slates). All three sections must be fitted correctly for the junction to be watertight.
Code 4 or Code 5 lead is standard for domestic chimney flashings. The lead is dressed using a wooden or plastic dresser tool to form it tightly against both the brickwork and the tiles or slates without splitting or cracking. Properly fitted lead at this junction should perform for several decades before needing attention.
With the brickwork complete and the lead in place, the top of the stack is finished with new flaunching - a mortar bed that holds the pots and sheds water outward from the stack. The flaunching is applied in layers to build up adequate thickness (at least 50mm at the edges), pressed tight against the pot bases and finished with a smooth, sloped surface.
Pots are set in the wet flaunching and checked for level and alignment. If the original pots are undamaged and the homeowner wants to keep them, they are cleaned and re-set. If they are cracked or the wrong type for the flue, new pots go on. On a redundant chimney, a capping cowl can go over the pot at this stage to prevent rain and bird entry without sealing the flue entirely.
Once the main structural work is done, any mortar joints on the lower part of the existing stack that are eroded but structurally sound are repointed at the same time. This avoids a return visit in twelve months to deal with pointing that was borderline at the time of the rebuild. The lead flashing chases are pointed in with an appropriate mortar, and the whole junction is checked for gaps.
At this stage, water is sometimes run over the stack from a hose to check for obvious gaps before the scaffold comes down. It is much easier to address a small issue at this point than after the scaffold is gone.
All debris - old bricks, broken pots, mortar arisings and packaging - is cleared from the roof and the area around the base of the scaffold before the platform is struck. Any tiles or slates disturbed when dressing the lead are re-bedded and checked. The gutters are cleared of any dust or mortar that has dropped in during the work.
The scaffold is taken down and removed, and the area is left clean. Before you accept the job as complete, walk around the property and look at the stack from the ground. The top should be level, the pots upright, and there should be no visible gaps in the flaunching or flashing.
A straightforward chimney rebuild on a standard two-storey property typically takes one to three days of active work, depending on the extent of the takedown and rebuild. Scaffold erection and strike add time at either end. Delays can occur if mortar needs to cure before subsequent work (particularly in cold or damp weather), or if materials need to be sourced specially for a matched brick type.
Typical costs for a chimney rebuild in mid-Norfolk range from around £1,500 for a small stack rebuilt above the flaunching line to £4,000 or more for a full stack taken down to the roofline with new lead flashing throughout. Scaffold hire and access is usually the biggest variable in the cost, particularly on taller or more complex properties.
We carry out chimney rebuilds in Necton and across the wider mid-Norfolk area, including Dereham and villages such as Yaxham. If your stack needs looking at, call us to arrange an inspection from close up - that is the only way to give you an accurate picture of what the job involves and what it will cost.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
