Chimneys take more weather than any part of a Medway roof. The repairs we do most, why failed pointing causes leaks, and when a chimney needs rebuilding.
A chimney is the most exposed thing on a house — four faces open to the weather, standing above the roof line where the wind is strongest. It's also where a lot of Medway leaks start.
Failed Pointing
The mortar between the bricks and under the ridge tiles weathers out over decades. Once it's gone, water gets into the joints, freezes in winter, and expands — which opens them further. Repointing is a straightforward job done before it gets bad, and a much bigger one after water has been getting in for years.
Flashing Failure
Where the chimney passes through the roof, lead flashing keeps the water out. It lifts, cracks or pulls away with movement over time, and the result is water tracking down the chimney breast and appearing as damp inside — often in a room nowhere near the chimney itself, which is why chimney leaks are so often misdiagnosed.
Chimney Pots And Caps
Cracked pots let water straight down the flue into the house. Unused flues should be capped — a cowl or cap keeps rain and birds out and stops a slow trickle you'd never connect to the chimney.
When A Chimney Needs Rebuilding
If the brickwork is spalling badly across the stack, if it's leaning, or if the top few courses have crumbled, repointing won't hold. Rebuilding the stack above the roof line — sometimes only the top section — is the only repair that lasts. We'll tell you honestly which category yours is in; a lot of chimneys people fear need rebuilding just need repointing.
Why Period Homes Need Care
Rochester, Chatham and Strood have a lot of Victorian and Edwardian stacks built with soft lime mortar and original leadwork. These need materials and techniques matched to what's there — cement pointing on an old lime-mortared stack traps moisture and causes the brick to spall. It's a common and expensive mistake.
Free chimney surveys across Medway, with photographs of what we find and a fixed written price.
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Costs and timings in this article are guides for Medway and Kent properties. Every roof is different — a survey is the only way to get an accurate figure.