Chimney Restoration
In North Wales
Modern, Heritage And Listed

The flaunching, the sloped mortar bed that holds the pots and sheds water off the top of the stack, is the single most common point of failure. It is a thin mortar detail, fully exposed, and once it cracks the whole stack starts to fill with water from above.

Rather than repeatedly re-flaunching, we cast a chimney cap made to measure for your stack, with the openings sized to your pots and a proper overhang and drip so rainwater is thrown clear of the brickwork instead of running down the face of it. It is a far longer-lived answer to the same problem.

On modern brick stacks, joints are raked out to a sound depth and repointed in a traditional sand and cement mortar, finished to match the existing joint profile so the chimney does not end up looking like a repair.

On heritage and listed buildings, and on soft stone and old lime-bedded brick, we point in lime. A lime mortar is softer than the masonry around it and stays vapour-open, so the stack can dry out and any movement is taken up by the joint rather than by the face of the stone. Using hard cement on those buildings does real and permanent damage, which is why the method is chosen to suit the building rather than to suit the van.

Rendered stacks are common across North Wales and on the Anglesey and Conwy coast, where render was used to keep driven rain out of exposed masonry. When it cracks or hollows, water gets behind it and the render then holds the wet against the brick instead of keeping it off.

We remove failed render back to sound masonry and re-render in traditional sand and cement, or in the Weber render system where a more flexible, water-shedding finish suits the exposure and the movement of the stack. Both are finished to blend with the rest of the building rather than left as an obvious patch.

Where frost and saturation have taken the bond out of the mortar and the face off the brick, repointing is no longer enough. In that case the stack is taken down to a sound course, the reusable brick or stone is set aside, and it is rebuilt with matching materials, a proper cap and new pots or terminals as needed.

Rebuilds are the point at which the flashings should always be renewed too, because the stack is accessible and the roof covering around it is already lifted. New lead soakers, front apron, side step flashings and a back gutter go in as part of the work across Bangor, Llangefni, Anglesey, Caernarfon, Conwy, Llandudno, Colwyn Bay, Denbigh and Betws-y-Coed.