The Joint Expert Statement in Property Disputes (CPR 35.12)

A joint statement of experts is the written record produced after the experts on each side of a dispute have met, discussed the technical issues and set out where they agree and where they do not. In property litigation it is directed under Civil Procedure Rule 35.12 and is often the most influential document in the case: judges read it before the reports, parties use it to decide whether to settle, and it fixes the ground for cross-examination. This guide explains when it is ordered, what it must contain, how the experts' discussion works and what an expert witness surveyor must not do while preparing it.

What CPR 35.12 actually requires

Rule 35.12 allows the court, at any stage, to direct a discussion between the experts to identify the expert issues in the proceedings and, where possible, reach an agreed opinion on them. The court can specify the issues to be addressed and may then direct the experts to prepare a statement setting out the issues on which they agree, the issues on which they disagree, and a summary of their reasons for disagreeing.

Two safeguards matter to litigants. Under CPR 35.12(4) the content of the discussion cannot be referred to at trial unless the parties agree, and under CPR 35.12(5) an agreement between the experts does not bind the parties unless they expressly agree to be bound. In practice, though, a party who ignores a point its own expert has conceded will struggle to run it at trial, which is why the document carries so much weight.

Practice Direction 35 fills in the detail: the purpose of the discussion is not to settle the case but to agree and narrow the issues, identify the reasons for any remaining disagreement, and flag further work that would resolve them. The full text of CPR Part 35 and Practice Direction 35 is published by the Ministry of Justice.

When is a joint statement ordered in property disputes?

Almost every multi-track property case with opposing experts includes a 35.12 direction, usually sequenced after exchange of reports and before trial. Typical examples include:

• Building defects and construction claims — whether the work fell below the required standard, what caused the defect, and the reasonable cost of remedial works. The panel's construction expert witnesses often narrow a long defects schedule to a few contested items here.
• Dilapidations — item-by-item agreement on breaches of repairing covenants and the cost of works. See dilapidations expert witness services.
• Valuation disputes — agreement on comparables, valuation date and method. See valuation expert witness services.
• Boundary disputes — agreement on the features on the ground and what the conveyance plans show. See boundary dispute expert witness services.

Where the parties share a single joint expert there is nothing to reconcile and no joint statement is needed; that route is explained in the guide to what a single joint expert is.

How the experts' discussion works in practice

The discussion can be in person, by telephone or by video call. Beforehand the parties' solicitors normally agree an agenda: a neutral list of questions, ideally framed so that each can be answered yes or no with a short explanation. The experts then work through the agenda together. For a building defects claim a well-run meeting typically covers the facts both experts accept, the technical standard that applies (Building Regulations, British Standards, manufacturer's instructions or relevant RICS guidance), whether the property meets that standard item by item, causation, the scope and reasonable cost of remedial works, and any further inspection or opening-up that would resolve a disagreement.

Unless the court orders otherwise or the parties agree, lawyers do not attend the discussion. If they do attend, PD35 says they should not intervene except to answer questions put to them by the experts or to advise on the law. Clients never attend. The experts are entitled — and expected — to reach their own conclusions without seeking their instructing party's approval.

What the joint statement of experts must contain

Practice Direction 35 requires the experts to prepare the statement within 7 days of concluding the discussion and to sign it as soon as practicable afterwards. A clear statement follows the agenda and, for each issue, records:

• Agreed — the point is settled between the experts and can be treated as common ground.
• Disagreed — with a concise summary of each expert's reasons. This is the part the judge reads most closely.
• Further action — any additional inspection, documents or testing that would resolve the point, and any further material issues the experts consider should be addressed.

Two further PD35 rules matter for surveyors. Experts must give their own opinions to assist the court and do not require the authority of the parties to sign the statement. And if an expert significantly alters an opinion from the one in their report, the joint statement must include a note or addendum explaining the change. Changing position after a better argument is put is what an independent expert should do, but the reasons must be on the record.

The statement is usually tabular and sits alongside each expert's Part 35 report; the report contents are explained in the guide to what a CPR Part 35 report contains, and the separate written-questions procedure in Part 35 questions to experts.

What experts and solicitors must not do

The courts have become markedly stricter about interference. In Andrews v Kronospan Ltd [2022] EWHC 479 (QB) the claimants' expert was excluded from giving evidence after it emerged that solicitors had been supplying detailed comments on successive drafts of the statement. The Technology and Construction Court Guide takes the same line: legal advisers should not be involved in negotiating or drafting it, and any input should be limited to identifying material the experts may have overlooked.

For a surveyor acting as an expert witness the practical rules are simple. Draft the statement with the other expert, not with the instructing solicitor. Do not send drafts to the client or its lawyers for approval, and do not treat the meeting as a negotiation on behalf of the party paying the fee. The overriding duty under CPR 35.3 is to the court, and the RICS practice statement for surveyors acting as expert witnesses reinforces it. An expert seen to have taken instructions on what to concede damages the client's case far more than any honest concession would.

Timescales and cost

The timetable is set by the directions order. Allow for the agenda to be agreed, the discussion itself (half a day to a day for a typical residential defects or dilapidations claim, longer where the schedule is extensive) and the 7-day drafting window.

The work is usually charged at the expert's hourly rate, which for chartered surveyors on the panel typically sits at £150–£300 per hour, within an overall fee of £5,000–£15,000 for a straightforward matter across the whole instruction. Preparing properly saves money at trial: every issue agreed will not be cross-examined on, and a statement that leaves only two or three live points often prompts settlement. The wider fee picture is in the expert witness cost guide, and the earlier steps — permission under CPR 35.4, choosing the discipline and the letter of instruction — in how to instruct an expert witness surveyor.

Expert witness surveyors for property disputes from Survey Merchant

Survey Merchant provides RICS chartered surveyors as expert witnesses for construction defect, dilapidations, valuation, boundary, party wall and surveyor negligence disputes across England and Wales. The panel's experts prepare CPR Part 35-compliant reports, take part in experts' discussions and joint statements under CPR 35.12, answer written questions and give evidence at trial. Survey Merchant matches the discipline to the dispute and quotes fixed fees for each stage. Visit the expert witness services page, call 0204 579 8270 or contact Survey Merchant with the directions order and a short outline of the issues to arrange an expert.