What is it?
A crack appearing above a door frame, often extending diagonally or vertically from the corners.
What does it look like?
[Insert Photos] Typically a thin to wide gap in the plaster or masonry above the door header.
Common causes
1. Lintel failure
2. Structural settlement
3. Seasonal expansion/contraction
4. Slamming of doors
How serious is it?
Rating: Medium Concern. While often cosmetic, it can indicate that the lintel supporting the wall above the door is failing.
How to tell which cause you have
Is the door sticking? If yes, it is likely structural or lintel-related. Is it just a hairline in plaster? Likely seasonal.
What should you do next?
Monitor the crack for growth. If it widens beyond 3mm or the door becomes difficult to close, consult a structural engineer.
Typical repair options
Lintel replacement, helical bar reinforcement, or simple plaster filling for cosmetic issues.
Typical repair costs (UK)
£200 – £1,500 depending on whether the lintel needs replacing.
Frequently Asked Questions
1. Is a crack above a door always serious? No.
2. Can I fix it myself? Cosmetic cracks, yes.
3. Does insurance cover this? Only if caused by subsidence.
4. How long do repairs take? 1-2 days.
5. Will it come back? Not if the underlying cause is fixed.