Chimneys and parapets
What should you ask if the coping stones on a parapet have open joints?
Ask about the joints in the coping, not only the flashing where the roof meets the wall. Copings cap the parapet, and open joints let rain into the top of the wall even when a flashing lower down looks tidy, which is not a failed parapet flashing and not a chimney pot. A survey sees the joints that were in view and does not lift the stones.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Coping stones, brick-on-edge copings and concrete copings all rely on the joint and the drip. When the joint is empty, water runs between the stones and into the parapet core, then out through the face or into the ceiling near the wall. Repointing those joints is not the same job as relining a gutter behind the parapet. A home survey from the street can often see a front parapet and often cannot see a rear one. Each run should be separated.
There is no standard price for repointing copings, and access over a pavement or a neighbour’s roof changes it. Do not let a flashing quote silently exclude the coping, and do not let a coping quote silently include a hidden gutter that nobody has seen. If stones are loose, that is more urgent than a hairline joint because a loose coping can fall. The survey does not test the restraint of every stone. Say which lengths were visible.
What should you ask your surveyor?
- Which parapet runs did you see, and were the coping joints open?
- Are any stones loose, or only the mortar?
- Are you separating the copings from the flashing and the gutter behind?
What are the typical next steps?
- Include coping joints in the mason’s or roofer’s brief.
- Do not stand on a parapet to prod a stone.
- Keep a hidden gutter, if there is one, as its own unseen item until someone looks.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Is a parapet a chimney?
No. It is a wall at the edge of the roof. It shares this topic because water gets in at the top. The survey should not call it a stack.
Does a damp patch below a parapet prove the coping?
It raises the coping, the flashing and the gutter as candidates. One patch does not pick the winner without a look.