Why chimney mortar fails first
A chimney stack stands proud of the roof and takes the full force of wind and driving rain on every face. Over the years, frost works into the joints, the lime or cement binder breaks down and the mortar starts to crumble, wash out or fall into the gutter. The bricks themselves often outlast several generations of pointing, which is why a timely repoint is usually far less disruptive than a rebuild.
Signs the joints need attention
- Mortar recessed well back from the brick face, or missing altogether.
- Sandy grit or small pieces of mortar collecting in gutters or on a flat roof below.
- Plants or moss rooting in the joints.
- Damp patches on the chimney breast inside after heavy rain.
- Loose bricks near the top of the stack or under the pots.
How we repoint a chimney
With safe access in place, the old mortar is raked or cut out to a sensible depth, taking care not to damage the brick arrises. The joints are brushed and dampened, then packed with fresh mortar in layers and finished to a profile that sheds water. The mix is chosen to suit the building: older, softer bricks generally want a more forgiving lime-based mortar, while a hard modern brick can take a stronger mix. Using mortar that's harder than the brick is a common mistake that pushes damage into the bricks themselves.
The rest of the stack
Repointing is rarely the only thing worth looking at once you're up there. The flaunching, the sloped mortar bed holding the pots, often cracks at the same time. Lead flashings at the base may have lifted or split. Unused flues can be capped with ventilation to stop rain dropping straight down. Our main chimney repair page covers rebuilds, capping and other work in more depth, and if water is already coming in, the leaking chimney page explains how the source is traced.
Access and timing
Most chimney repointing needs scaffold, especially on two-storey houses or where the stack sits in the middle of the roof. Mortar needs reasonably mild, dry conditions to cure, so we avoid frosty spells and heavy rain. Small stacks can often be completed in a day or two once access is up; larger or shared stacks take longer.
What it costs
We don't publish prices because height, access, the number of faces and the condition of the brickwork vary so much. Our chimney repointing cost guide walks through each factor so you can compare quotes on a like-for-like basis.
Book a free quote
We cover homes and commercial buildings across Somerset and Devon, within about 50 miles of Taunton. Call 07399 680142 or send us your details, ideally with a photo of the stack.