Chimney repointing and rendering

A chimney stands above the roofline on its own, exposed on four sides to wind driven rain, and on most Irish houses it is the first part of the roof to fail. The signs usually show inside: a damp patch on the chimney breast in an upstairs room, staining on the ceiling beside it, or a fireplace that smells musty after rain. Outside you see cracked or missing render, open mortar joints, cracked flaunching around the pots, and flashings that have lifted or been smeared with sealant. We work off scaffolding, because a stack is heavy, high and awkward, and good work cannot be done one handed from a roof ladder. Loose render is hacked off rather than patched, open joints are raked out and repointed, and the stack is rerendered in a mix that suits what it is built of, since older brick and stone stacks need a softer, breathable mortar rather than hard cement. The flaunching at the top is renewed so water runs off the stack instead of soaking in, and pots are rebedded or capped. Unused flues get a ventilated cap that keeps the rain out while letting the flue breathe, because sealing a flue completely traps condensation inside it. Where the stack meets the roof, lead flashings are cut into the joints and dressed down properly, with a back gutter behind the stack where the roof runs into it.

Is it the chimney, or something else?

A damp chimney breast is not always rain. Condensation inside a sealed flue, a missing damp proof course in the stack, or salts left by years of burning coal can all show the same stain. We look at the stack, the flue and the room before quoting, so you pay to fix the actual cause.