CPR Part 35 expert evidence in professional negligence claims against surveyors — missed defects, negligent valuations, and what a reasonably competent surveyor would have done.
A surveyor negligence claim turns on one question: did the original surveyor fall below the standard of a reasonably competent member of the profession? Only another surveyor can answer it — which is why the courts expect expert evidence in almost every claim of this kind. Our RICS surveyors and Registered Valuers act as expert witnesses on both sides of surveyor negligence disputes across England and Wales.
Negligence claims the panel's experts give evidence in
- Missed defects in home surveys — damp, timber decay, roof failures, structural movement and subsidence that a competent Level 2 or Level 3 inspection should have identified or flagged for investigation.
- Negligent valuations — figures falling outside the reasonable margin of error, examined by an RICS Registered Valuer alongside our valuation expert witness team.
- Party wall surveyor negligence — defective awards, missed notices and procedural failures that caused loss.
- Defence instructions — acting for surveyors and their insurers where the claim overstates what an inspection of that type could reasonably find.
- Causation and quantum — what the claimant would have done with a competent report, diminution in value, and the cost of repairs.
How the negligence test actually works
The benchmark is not perfection and it is not hindsight. A Level 2 survey is a visual inspection; a surveyor is not negligent for missing what that level of survey could not see. The expert's task is disciplined peer review: reconstruct what was visible on the day, apply the standards and guidance in force at the time, and say — with the independence CPR Part 35 demands — whether the original work fell short. That independence cuts both ways: our experts regularly advise claimants that a claim is weak before costs escalate, which is exactly what early expert advice is for.
Instruction and fees
Party-appointed and Single Joint Expert instructions are accepted from solicitors, insurers and litigants. A screening review of the original report and file typically costs £500–£1,500 and tells you whether the claim has legs; full Part 35 reports generally run £5,000–£12,000 — see the expert witness cost guide and our explainer on what a CPR Part 35 report contains.
Frequently asked questions
Can I sue my surveyor for missing a defect?
Only if a reasonably competent surveyor carrying out that level of survey would have found or flagged the defect — a Level 2 survey is a visual inspection, so not everything missed is negligence. Claims generally must be brought within six years, or three years from when you could first have known of the problem, subject to a 15-year longstop. An expert screening review of the original report is the quickest way to test whether a claim has merit.
What is the test for surveyor negligence?
Whether the surveyor fell below the standard of a reasonably competent member of the profession, judged by the standards and guidance in force at the time — not by hindsight, and not against perfection. Because only a surveyor can say what a competent peer would have done, courts rely on expert evidence to establish breach in almost every surveyor negligence claim.
How much does an expert report for a negligence claim cost?
A screening review — the original report, photographs and file examined against competent practice, with a view on merits — typically costs £500–£1,500. A full CPR Part 35 report generally runs £5,000–£12,000 depending on the property and issues. Screening first is almost always the right order: it prevents spending litigation money on a claim an expert would not support.