If your chimney in Newmarket is showing cracks, leaning brickwork or staining on the breast inside, a rebuild from the roofline up is very likely what it needs.
Repointing and patching have their place, but there comes a point where the stack itself has deteriorated so far that cosmetic repairs just delay the inevitable. A chimney rebuild means taking the structure down to a sound course of brickwork at or just above the roofline and rebuilding it correctly from there. We do this across Newmarket and the surrounding area, using matching bricks, properly installed lead flashings and a new damp-proof course (DPC) where required.
The question most homeowners face is working out whether what they can see actually warrants a rebuild or whether a repair will do. The warning signs below will help you make that judgement before you call anyone.
Spalling is when the face of the brick breaks away, leaving a rough, pitted or flaking surface. It happens when water gets into the brick, freezes and expands, then breaks the surface off when it thaws. One or two spalled bricks in an otherwise sound stack can be cut out and replaced. When spalling affects a large portion of the stack above the roofline, the structural integrity of the brickwork is compromised and rebuilding is the only lasting solution.
A chimney that is visibly leaning, tilting or has moved off-plumb is a serious structural problem. The cause is almost always failed mortar joints combined with the weight of the stack acting over years of freeze-thaw cycles. Gravity does the rest. A leaning chimney above a bedroom or a roof slope is a safety risk and should not be left. Patching the mortar on a stack that has already moved will not correct the lean - the stack needs to come down and go back up plumb.
Mortar joints are what bind the bricks together and shed water away from the stack. When the joints erode back more than about 10-15mm across a significant proportion of the stack, water tracks straight into the core. You might notice this as damp patches on the chimney breast inside, staining on the ceiling around the flue, or efflorescence (white salt deposits) on the outside face of the brickwork. Raking out and repointing is viable on a sound stack, but when the joint failure is widespread and the bricks themselves are damaged, rebuilding gives you a sound structure rather than a patched one.
Lead flashings seal the joint between the chimney stack and the roof covering. When they pull away, crack or were installed poorly in the first place, rainwater tracks down behind the slates or tiles and into the roof space. You may see water marks on the rafters or on the ceiling below. Flashings can sometimes be re-dressed or replaced in isolation, but if the brickwork they are fixed into is also in poor condition, the sensible approach is to rebuild the stack and install new lead at the same time - otherwise you are fixing the flashing into brickwork that will need attention again soon anyway.
The haunching is the mortar fillet that holds the pot to the top of the stack. When it cracks - which it does as the stack moves and as frost gets in - water enters the core of the stack from the top. A cracked pot and failed haunching on top of already damaged brickwork is a combination that pushes a job from repair territory into rebuild territory.
Damp around a chimney breast is one of the most common reasons homeowners call a roofer. The cause is not always obvious from inside. Water could be coming in through the flashings, through the mortar joints, through the pot, or through all three at once. Getting on the roof to inspect the full stack is the only way to know for certain. Do not let a roofer diagnose a chimney problem from the ground alone.
The position of a chimney makes it one of the most exposed parts of any house. Rain hits it from all sides, frost cycles put the brickwork under repeated stress, and the daily and seasonal temperature change causes mortar to expand and contract. Over decades this movement slowly opens up joints and works moisture into the structure.
Older lime-based mortars are actually more tolerant of movement than harder modern mortars - if an older stack has been repointed with an overly hard cement mix, the mortar can hold fast while the bricks crack around it. This is a common cause of accelerated brick failure on older stacks.
Chimneys that are no longer used are also vulnerable. Without the warmth of a working flue helping to dry the stack from the inside, moisture accumulates more easily. Capping off an unused chimney without ventilating it properly can make this worse.
We take the stack down, carefully, to a sound course of brickwork just above or at the roof level. We then rebuild using bricks that match the existing as closely as possible, with fresh mortar at the correct mix for the age and type of original construction. A new lead flashing is installed at the junction with the roof, and a DPC is built in to prevent ground-level damp rising up the stack. The pot is seated and haunched with fresh mortar at the top.
Scaffold or a safe working platform is always required for this type of job - a chimney rebuild cannot be done safely from a ladder.
A straightforward chimney rebuild on a two-storey house typically takes one to two days on the tools once the scaffold is up. The total time from scaffold erect to scaffold strike will vary depending on the contractor's schedule and drying time for the mortar.
A chimney rebuild is priced by the size and height of the stack and by how much of it needs to come down. As a guide, a partial rebuild on a standard two-storey semi-detached house - taking the stack down to just above the flashing line and rebuilding with new lead - typically costs in the region of £1,500 to £3,500 including scaffold. Larger stacks, awkward access or the need for specially sourced matching bricks will push the cost higher. Get at least two prices and make sure each quote specifies what is and is not included.
If you are not sure whether your chimney needs a rebuild or a repair, call us and we will tell you honestly what we can see. We are based in Ely and cover a wide area including Mildenhall, Ely itself, Stretham and further afield.
Call us for a roof survey in Newmarket and we will give you a straight answer on whether a rebuild is necessary and what it will realistically cost.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
