What happened: The High Court enforced an £8.7 million adjudication award against project manager Avison Young over negligent over-certification of earthworks payments on a Coventry development
Who's involved: Coventry & Warwickshire Development Partnership (employer) and Avison Young (UK) Limited (project manager)
What's at stake: £8,729,179.33 plus interest in damages for professional negligence
Why it matters: PI underwriters and claims handlers should note the court's robust enforcement of a negligence-based adjudication award - and the exposure when a contractor goes bust before overpayments can be clawed back
Where it stands: Summary judgment granted; adjudication award enforceable (parties may pursue final determination in later proceedings)
Five million cubic metres of earth, a contractor that went bust, and a project manager left holding an £8.7 million bill.
That is the result of a High Court ruling that enforced an adjudication award against Avison Young (UK) Limited - and it carries pointed lessons for anyone underwriting or handling professional indemnity claims in construction.
The dispute centres on Gateway South, a 215-acre industrial and logistics park in Coventry built on the site of a former sewage treatment plant. The development required massive earthworks: excavation, treatment, and repositioning of roughly five million cubic metres of material to form an environmental bund. Coventry & Warwickshire Development Partnership LLP hired a contractor, Buckingham Group Contracting Ltd, to carry out the work and appointed Avison Young to oversee it as project manager and supervisor.
Avison Young's job included certifying how much the contractor was owed at each monthly payment stage.
Under the contract, the amount owed at each stage was worked out by calculating what share of the total work had been completed and applying that proportion to the agreed lump sum price. To get the figure right, the project manager needed to know three things: the total volume of work required, how much had actually been done, and whether any of the completed work was defective.
The development partnership said Avison Young got all three wrong. It alleged the project manager accepted reduced baseline volumes from Buckingham without questioning them - which made the contractor's progress look greater than it actually was. It also said Avison Young took the contractor's progress claims at face value, even though other data in its own possession painted a different picture. And it said defects in the completed work went unidentified.
When Buckingham went into administration in 2023, the development partnership was left with what it described as a £25.4 million overpayment and no realistic way to recover the money from the insolvent contractor. So it turned to the project manager who had certified the payments.
An adjudicator - the decision-maker in the fast-track dispute process commonly used in construction - awarded the development partnership £8,729,179.33 plus interest as damages. That figure reflected the adjudicator's own assessment of the loss, which was lower than the amount originally claimed because he rejected some of the defects arguments and adjusted for factors like retention money.
Avison Young refused to pay. It argued the adjudicator had addressed the wrong question - essentially conducting a valuation exercise rather than assessing whether the project manager had been negligent. It said the adjudicator had not given adequate reasons for the decision. And it said there had been a breach of fair process, because the adjudicator had relied on a termination account prepared by quantity surveyors Gardiner & Theobald without giving the parties a proper opportunity to respond.
The court in London's Technology and Construction Court rejected every argument.
On the question of whether the adjudicator had addressed the right dispute, the judge found he clearly had. The adjudicator had identified the issue - whether Avison Young had failed to carry out its duties with proper care and skill - and had worked through breach, cause, and resulting loss, even if the structure of his reasoning did not separate those elements into neat sections. Crucially, the adjudicator had rejected some of the defects claims on the basis that certain problems were not ones a competent project manager could reasonably have been expected to spot. That distinction showed he was assessing professional conduct, not simply recalculating what the contractor was owed.
On fair process, the court found the adjudicator had given ample warning that he might use the Gardiner & Theobald assessment. He had flagged it, explained why he thought it was relevant, invited submissions from both sides, and offered a joint meeting. Avison Young had argued the assessment should be disregarded but had not put forward an alternative case for what should happen if the adjudicator disagreed. That was a tactical choice, the court said, not a basis for alleging unfairness.
A separate attempt to carve out parts of the award - specifically, how the adjudicator handled retention money and defects - also failed. The court found those elements were part of an interconnected chain of reasoning that could not simply be unpicked and recalculated.
The ruling reaffirms what the construction sector already knows about adjudication enforcement: the bar for resisting payment is high. Courts have consistently said that technical defences should be examined with scepticism, and that trawling through an adjudicator's reasoning to find grounds to avoid paying is exactly the approach the statutory scheme was designed to discourage.
For PI insurers and claims teams, the practical point is this: over-certification risk does not disappear when the contractor leaves the site. When insolvency closes the door on recovering the overpayment from the contractor, the professional who signed off on the numbers becomes the target - and adjudication, typically used for payment disputes between contractors and employers, proved here to be a viable route for a professional negligence claim worth nearly £9 million.
The adjudication award has been enforced by the High Court. Avison Young retains the right to challenge the underlying decision in separate legal or arbitration proceedings, as adjudication decisions are not final determinations of the parties' rights.
