A delay analysis can be technically sound and still run into difficulty in adjudication if the contractual basis of the claim is unclear, the wrong party refers it, or a decisive issue is resolved without giving both parties a chance to respond.

Four recent decisions illustrate those points. Entexol and Premier Modular concern delay directly. Avison Young and Darchem do not, but their lessons apply just as readily when a programme or delay analysis is put before an adjudicator.

While planning and programming experts often view their role as strictly quantitative, measuring critical path movements in scheduling software, these judgments demonstrate that technical methodology is only as good as the contractual scaffolding supporting it.

An adjudicator can take a different route

In Coventry & Warwickshire Development Partnership LLP v Avison Young (UK) Ltd [2026] EWHC 2319 (TCC), the adjudicator relied on an assessment that neither party had advanced as the basis for its case. Avison Young argued that this breached natural justice.

The court disagreed. The adjudicator had identified the assessment, explained why he considered it relevant and invited the parties to comment. They had a fair opportunity to address the approach he might take, and the court enforced the award of approximately £8.7 million.

The same issue can arise in a delay dispute if an adjudicator asks about a programme, progress record or alternative assessment that neither expert has adopted. A party may need to do more than argue that the material should be disregarded. It should consider explaining what follows if the adjudicator decides to use it. In Avison Young, the court noted that the responding party had chosen not to advance an alternative case on that footing.

 

What's the practical lesson for delay analysts? 

If the choice of programme is disputed, consider setting out a clearly labelled alternative analysis in the report. Explain what changes if the other programme is used: the relevant progress, the critical path and the resulting delay. State that this is a conditional calculation and does not change your primary opinion.

The same approach matters if an adjudicator later asks whether a contemporaneous progress update gives a better picture than the programme used by either party. Simply repeating that it is the “wrong” programme leaves the question unanswered. Explain what the update shows, its limitations and what result follows if the adjudicator relies on it.

That gives the adjudicator an evidenced route to a different conclusion and gives the other party an opportunity to address it, rather than leaving the adjudicator to construct an untested calculation.

An adjudicator can reject the basis of a claim

Entexol Ltd v Sked Construction Ltd [2026] CSOH 80 concerned a delay contra-charge. Sked argued that an email sent during the works had fixed 13 November 2024 as the subcontract completion date. Its claim for delay costs depended on that date.

The adjudicator rejected Sked’s position. He found that the email did not establish the asserted completion date and that there was no evidence Entexol had agreed to it. He described time as being at large and rejected the contra-charge.

Sked resisted enforcement, arguing that neither party had advanced a case based on time being at large. The Court of Session disagreed. The adjudicator’s reference to time at large followed from his rejection of the date on which Sked’s own case depended. He did not have to warn Sked that its argument might fail and invite a further case.

 

What is the practical lesson for delay analysts?

Before analysing the effect of alleged late completion, establish the contractual basis for the date relied upon. Sked’s contra-charge depended on its asserted completion date. Once that date was rejected, any delay contra-charge would have needed a different footing, such as a failure to complete within a reasonable time, and Sked had not advanced one.

This is an important limit on what a programme can prove. A report should state where its completion date comes from - the original subcontract, an agreed amendment, an instruction, or another identified document. If that date is disputed, the report should explain which conclusions depend on it and which, if any, survive under the alternative case actually advanced by the party.

Parties must have a chance to address a new basis for the decision

Premier Modular Ltd v Maidstone and Tunbridge Wells NHS Trust [2026] EWHC 1404 (TCC) provides the contrast. The dispute concerned an NEC4 compensation event arising from the timing of a permanent water supply where the provision of permanent water supply wasnot identified in the Accepted Programme. The adjudicator found a compensation event on a contractual basis neither party had argued. He also treated the Accepted Programme as having been updated, contrary to the position both parties had taken. 

Those findings were central to his decision, but the parties had not been given an opportunity to address them. The court found that the Trust had a real prospect of establishing a material breach of natural justice and refused Premier Modular’s application for summary judgment to enforce the award.

For delay practitioners, the programme point is significant. Which programme was accepted, what it showed, whether a later submission changed that position and whether it was prepared appropriately, regardless of being accepted, can affect both the contractual basis and the assessment of a compensation event. A delay report should make clear which programme it relies on, why it is relevant and what difference a disputed programme status makes to its conclusions.

What is the practical lesson for delay analysts?

“Latest programme” and “Accepted Programme” are not interchangeable descriptions. In an NEC dispute, record the revision, data date, submission date and response to each programme relied upon. If acceptance is disputed, or if a non-accepted programme has been used to produce the analysis, distinguish the programme’s contractual status from its usefulness as evidence of planned work or actual progress.

The programme does not need to be accepted to be a contemporaneous record useful in preparation of delay analysis. That distinction can be set out briefly, but it must be explicit. Otherwise, a reader may be unable to tell whether an analysis depends on a contractual premise, a factual reconstruction, or both.

Check who can bring the claim

Darchem Engineering Ltd v Bouygues Travaux Publics and Laing O’Rourke Delivery Ltd [2026] EWHC 220 (TCC) concerned jurisdiction, not delay analysis. Darchem, one member of an unincorporated joint venture, commenced adjudication in its own name and obtained a decision worth approximately £23.9 million. The court refused enforcement: under the subcontract, Darchem alone did not have the right to refer the dispute to adjudication.

The point applies to any claim, including one supported by extensive programme evidence. Before commissioning a substantial delay submission, confirm who holds the contractual right to bring the dispute.

What is the practical lesson for delay analysts?

The practical check is especially relevant where a project has joint ventures, novations or several related contracts. Identify the contracting parties, the party named in the notice of adjudication and the party entitled to the remedy sought. If those do not align, that issue needs resolving before the technical submission is assembled, regardless of the instruction given by the instructing party.

 

What does this mean for a delay report?

These cases show why the report and the claim around it need to withstand several different questions:

• Contract - What is the basis for the completion date and entitlement claimed?
• Programme - Which programme is relied upon, and what is its contractual status?
• Evidence - How did the event affect the works, and what delay did it cause?
• Alternatives - What follows if a disputed date, programme or assumption is rejected?
• Referral - Is the party bringing the adjudication entitled to do so?

A practical way to answer those questions is to include a short assumptions and alternatives section alongside the delay analysis. Note, that this is not an invitation to invent fallback claims but a way to expose the assumptions on which the opinion depends and to address alternatives that are genuinely in issue.

Best, Radek Makar Director | ViViAD radek@viviad.co.uk

ViViAD is an independent consultancy specialising in Planning, Project Controls, Power BI Reporting, and Construction Claims Support. We work across the UK - typically on NEC contracts in defence, nuclear, renewables, and infrastructure - embedding with project teams to bring structure, clarity, and commercial control. Interim or longer-term, we fit around what you need.