Age and type of house
What should you ask if a concrete lintel is cracked and stained with rust?
Ask whether the surveyor can see the lintel itself and how far the crack runs. Rust-coloured cracks in concrete over a window often mean the steel inside the concrete is corroding and expanding. That is a lintel defect. It is not automatically subsidence. A home survey does not break the concrete open to measure the bar.
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?
The usual picture is a horizontal crack through the lintel, with orange staining, sometimes a slight drop at the opening. The Association of British Insurers’ subsidence description is about the ground. Use it only if the rest of the wall matches. Approved Document A does not grade this lintel. A visual survey records the crack and the limit.
A builder may need to prop the opening before cutting the concrete out. There is no RICS price for that. Do not rake the crack and fill it the weekend you move in. Filling hides the stain the next person needs. If several lintels on one elevation look the same, say so. Do not multiply one crack into every window without looking.
What should you ask your surveyor?
- Which openings show rust cracking, and which do not?
- Is the masonry above the lintel disturbed?
- Are you distinguishing this from foundation movement?
What are the typical next steps?
- Photograph each affected opening. Do not assume the whole house matches.
- Ask a builder what propping they would need before they quote.
- Do not call it subsidence in the price negotiation unless the survey did.
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 hairline in the paint the same as a cracked lintel?
No. Paint cracks. The comment is a crack in the concrete, especially with rust staining.
Does one rusty lintel mean the concrete floors have failed?
No. A window lintel is not a floor. Do not generalise.