A survey flagging structural movement or subsidence is alarming, but it's not automatically a deal-breaker. The key is understanding what type of movement it is, whether it's active or historic, and what the structural risk is. That assessment requires a structural engineer — not just a RICS surveyor.
What your surveyor is telling you
RICS surveyors are trained to identify signs of structural movement and flag them. They're not structural engineers. When a survey says "we recommend a structural engineer's report on the cracking observed to the rear elevation," they're saying: there's something here that needs specialist investigation.
Visible cracking can mean many things:
- Normal thermal expansion and contraction in the building fabric
- Historic movement that settled years ago and is now stable
- Active ongoing subsidence requiring investigation and possible remediation
You cannot tell which category applies from the survey alone.
Getting a structural engineer's report
Commission an independent structural engineer (not one recommended by the seller). A MICE or MIStructE qualified engineer will:
- Inspect the building thoroughly — including external elevations, internally through the loft, and any cellars or undercroft
- Assess the type, pattern, and severity of cracking
- Determine whether the movement appears active or historic
- Recommend monitoring, investigation, or remediation as appropriate
- Advise on likely cause
The report takes 1–3 hours to complete on site and 1–2 weeks to receive in writing. Cost: typically £700–£1,500.
What the report might say
Historic, stable movement: The property has settled in the past (often decades ago) and is now stable. No active risk. This is the best outcome — it often means the purchase can proceed, sometimes with specialist indemnity insurance.
Active movement, cause identified: The ground is moving, but the cause is identifiable and treatable — a leaking drain, a large tree in proximity, clay shrinkage from last summer's drought. Treatment can be arranged; costs are quoted.
Active movement, cause unclear: Further investigation required — possibly crack monitoring over 6–12 months, or drains survey. This is a difficult situation for a buyer: you may need to wait for results before being confident to proceed.
Significant structural concern: The movement is severe and the structural integrity of the building is compromised. Remediation costs could be substantial. This is rare in residential property but does happen.
Using the report to negotiate
If the structural engineer identifies a treatable cause with quoted remediation costs, you have the basis for renegotiation. The cost of underpinning, drain repair, or tree removal is your leverage.
If the engineer recommends monitoring before any conclusion can be reached, you have a decision to make: wait for monitoring results (possibly 6–12 months, during which you'd lose other opportunities) or walk away.
This Q&A is for general information. Dom does not provide legal or structural advice. Consult a qualified structural engineer for assessment of any specific property.