Chimney repairs in Leatherhead, Surrey and South West London

Where Most Roof LeaksActually Start.

When the brickwork has gone, the stack is rebuilt from sound brick down, with a new lead tray and flashings, new pots and cowls, and a proper flaunching on top to shed the water.

When the brickwork has spalled or the stack is leaning, repointing is not enough. We take the stack down to sound brick, rebuild it to the original profile, fit a lead damp proof tray through it at roof level, new flashings around it, new pots and cowls, and a flaunching that sheds the water.

A rebuild uses reclaimed brick to match the house where the stack is seen from the street, a lead damp proof tray at roof level with weep holes, new pots bedded in a fresh flaunching, and new flashings around the base. A typical stack is rebuilt in two to three days.

Cracked pots replaced. Cowls fitted to stop rain and birds. Unused flues capped and vented so they stay dry without trapping damp in the stack.

A cracked pot lets water into the flue and eventually into the room below. A missing cowl lets rain and birds in. An unused flue that is capped without a vent traps damp and shows as a stain on the chimney breast. Each is a small job done from the roof while the scaffold or ladder is there.

A flue that serves a gas appliance needs the right terminal for the appliance, and a Gas Safe registered engineer signs off anything that affects it; we work with them where a chimney serves a boiler. A redundant flue is capped with a vented cap so the stack stays dry inside.

The lead where the stack meets the roof is the commonest leak on a house. We form new step flashings, back gutters and aprons, and fit a lead tray through the stack where there is not one.

Most damp on a chimney breast is the lead rather than the brick. New step flashings, a back gutter and an apron formed on site stop the water at the roofline. Where the stack has no lead tray we fit one through the brickwork so water that gets into the stack above the roof cannot come down inside.

A lead tray through the stack is fitted at the level of the roof, stepped to the pitch, with the brickwork rebuilt above it. It stops water that soaks into the exposed brick above the roof from tracking down inside the chimney breast, which is the cause of the damp on many older houses.

A stack that is leaning, unused and past repair is safer off the roof. We take it down to below the roofline, make good the roof, and leave nothing to worry about in the next storm.

A redundant stack that is leaning or crumbling is a risk in every storm and costs money to keep. Taking it down to below the roofline, capping the flue and roofing over the opening removes the problem for good, and it often costs less than rebuilding.

Removing a stack to below the roofline is usually a two day job: the brick comes down, the flue is capped, the roof is timbered, felted and tiled across the opening, and the finished slope is photographed. Where the stack is shared with a neighbour, the party wall side stays as it is.