Cracks Appearing During Your Neighbour’s Building Work: What Should You Do?
There is something particularly unsettling about discovering a crack in your home while building work is taking place next door. Perhaps you have noticed a fine line above a doorway that you cannot remember seeing before. Maybe a crack has appeared along the ceiling, or a door that previously closed without difficulty has started sticking.
It is natural to wonder whether your neighbour's builders are responsible.
However, discovering damage during construction and establishing what caused it are two different matters. Buildings can develop cracks for several reasons, including temperature changes, ordinary settlement, moisture movement and alterations to the structure.
The important thing is to respond sensibly, preserve evidence and understand the options available to you.
At Adam Joseph Chartered Surveyors, we help property owners understand the Party Wall etc. Act 1996 and the procedures available when neighbouring building work raises concerns.
1. Start by recording what you have discovered
Before arranging repairs or confronting your neighbour, take photographs of the affected areas.
Photograph the crack from a distance to show its location within the room, then take closer images showing its appearance. Include a ruler or measuring scale where practical.
Record the date when you first noticed it, along with any relevant observations, such as whether excavation, drilling or structural alterations were taking place next door.
You may also want to note:
- Whether the crack appears above a doorway or window.
- Whether it runs diagonally, vertically or horizontally.
- Whether it affects plaster only or appears to extend into masonry.
- Whether nearby doors or windows have become difficult to operate.
- Whether there are corresponding cracks externally.
Avoid filling or decorating over the area until suitable evidence has been recorded.
If cracks are widening rapidly, accompanied by significant movement or other signs of structural instability, seek urgent advice from an appropriately qualified structural engineer. Do not enter an area that appears unsafe.
2. Check whether a Schedule of Condition was prepared
A Schedule of Condition can become extremely useful when a neighbour raises concerns about building-related damage.
This document records the visible condition of relevant parts of a neighbouring property before construction starts, usually through photographs and written observations.
For example, a report might identify an existing hairline crack in the hallway ceiling, older decorative damage around a window or previous repairs to masonry.
If you discover a crack after work begins, the original record helps establish whether that particular defect was already present.
It is important to understand that a Schedule of Condition does not guarantee protection against damage. Its principal value is evidential.
If no report was prepared, that does not automatically mean you cannot pursue a legitimate concern. It may simply make the assessment more difficult.
3. Find out whether the Party Wall Act applies
Not every construction project falls under the Party Wall etc. Act 1996.
The Act generally concerns specified works involving party structures, new walls at or astride boundaries, and certain excavations close to neighbouring buildings.
Examples include cutting into a shared wall to accommodate structural beams, demolishing and rebuilding a party structure, and digging foundations where the statutory distance and depth conditions are met.
A standard internal refurbishment entirely within the neighbour's property may fall outside the Act.
This distinction matters because the route for dealing with damage may differ depending on whether the works are notifiable and whether surveyors have been appointed.
For general background, read Adam Joseph's existing guide to adjoining owner's rights.
4. Speak to your neighbour before the situation escalates
Many disagreements become unnecessarily difficult because the first conversation happens after frustration has built up.
Approach your neighbour calmly, explain what you have noticed and ask whether the builder or project manager can provide information about the current stage of construction.
Try not to assume that the builders must be responsible before the defect has been assessed.
A useful approach might be to explain that you have discovered a crack, have photographed it and would appreciate an inspection to establish whether any construction-related movement may have occurred.
Keep a written record of important conversations and correspondence.
If the works have an appointed party wall surveyor, notify the relevant surveyor promptly.
Communication does not replace professional assessment, but it can help prevent a manageable problem from becoming a prolonged disagreement.
5. How do surveyors decide whether construction caused damage?
A surveyor may review the available Schedule of Condition, dated photographs, construction drawings, the sequence of works and the nature of the reported defect.
The position and appearance of a crack may offer clues, but appearances alone rarely establish causation conclusively.
For example, a small plaster crack near a ceiling joint could arise from historic movement or normal material changes. A new pattern of cracking appearing alongside measurable displacement might require a more detailed investigation.
Sometimes a structural engineer's opinion is necessary, particularly where the issue involves possible foundation movement or changes to load-bearing elements.
The objective is to reach a reasoned conclusion supported by evidence.
Where an Award is in place, the surveyors may have a role in determining matters arising from damage associated with the notifiable work.
For other building-related damage, different legal remedies may need consideration.
6. Who pays for repairing the damage?
If damage is established to have resulted from works covered by the Party Wall Act, the Act provides mechanisms addressing compensation and making good damage.
The specific outcome will depend on the circumstances, the applicable statutory provisions and any relevant Award.
It is not correct to assume that every mark discovered during building work will automatically be repaired at the building owner's expense.
Equally, an adjoining owner should not assume that they must pay to repair damage simply because their neighbour disputes responsibility.
Evidence, causation and the nature of the works are central to resolving the issue fairly.
If the surveyors cannot resolve a particular issue, professional legal advice may be appropriate.
7. What happens if your neighbour did not serve a Party Wall Notice?
Some homeowners discover that potentially notifiable construction has already started without any notice.
The absence of a required notice is a serious procedural concern, but the Act does not give surveyors an unlimited power to retrospectively authorise completed works or determine every kind of dispute.
If work is ongoing, obtain advice promptly about the statutory position, the evidence needed and any appropriate legal remedies.
Do not rely on verbal assurances that a notice is unnecessary simply because the work is taking place within the neighbour's boundary.
A qualified surveyor can review the drawings and circumstances to help identify whether the Act is relevant.
8. Can you prevent similar disputes in future?
Prevention usually starts well before excavation or structural work begins.
If your neighbour is planning a major extension, ask for a reasonable explanation of the works and take the time to read any Party Wall Notice properly.
Where a dispute arises under the Act, surveyors can deal with relevant statutory matters and may arrange a Schedule of Condition.
For homeowners planning construction themselves, early communication is equally valuable.
As Adam Joseph explains in its article about preventing party wall disputes, careful planning and constructive communication can reduce unnecessary conflict.
9. When should you contact a party wall surveyor?
Seek professional advice when you are uncertain about the status of a notice, believe work may affect a shared structure, or need help understanding the surveyor's role in a damage dispute.
A party wall surveyor does not replace a structural engineer, a building insurer or a solicitor. Different professionals address different aspects of a problem.
The first step is establishing the right procedure for your situation.
Adam Joseph Chartered Surveyors assists building owners and adjoining owners with Party Wall Notices, Schedules of Condition and Party Wall Awards.
If you have noticed cracks during neighbouring construction, you can contact Adam Joseph Chartered Surveyors to discuss the circumstances and obtain guidance on the appropriate next steps.
The priority should always be protecting safety, maintaining reliable evidence and resolving the issue on its merits rather than allowing assumptions to determine the outcome.
For friendly professional advice, contact Adam Joseph Chartered Surveyors or call 020 3875 9279 now to speak with a specialist Party Wall Surveyor.










