Disputes & Recovery

How an NEC adjudication actually runs

NEC adjudication runs faster than most teams’ commercial cycles, and its outcome usually sticks. Here is what the W2 procedure actually says, where parties keep getting caught, and what disciplined adjudication practice looks like.

4 May 2026 · 9 min read · Free to read

Executive summary

Most NEC contracts in the UK contain Option W2. Most teams treat adjudication as something that happens to other programmes, then panic the morning a notice of intention to refer arrives. The clauses tell a clearer story: a fast, formal, statutory mechanism whose outcome usually sticks.

This post walks the W2 procedure as it actually runs on a live programme. The notice of intention, the 28-day decision clock and its 42-day reality, the Senior Representatives circuit-breaker introduced in NEC4, and the temporary-final nature of the Adjudicator’s decision. Then where it fails in practice, and what good looks like.

Clause analysis

The disputes & recovery clause analysis

Option W2: when it applies

Option W2 is the NEC4 dispute-resolution route for UK construction contracts subject to the Housing Grants, Construction and Regeneration Act 1996 (the Construction Act, as amended). The Act requires that the right to adjudicate be available at any time, and W2 substitutes a compliant procedure where the contract’s bespoke wording would otherwise fall short.

The notice of intention

The first procedural step is the notice of intention to refer: a written notice to the other party identifying the dispute. The notice itself starts the clock. Anything not framed as part of the dispute in the notice is at risk of being held outside the Adjudicator’s jurisdiction later.

Appointing the Adjudicator

If an Adjudicator is named in the Contract Data, that person is approached first. If no Adjudicator is named, or the named Adjudicator cannot act, the Adjudicator Nominating Body identified in the Contract Data nominates one. The nomination is the only practical reason to negotiate the Nominating Body at contract signature; in disputes, the body’s selection panel meaningfully shapes outcome variance.

The 28-day clock (and the 42-day reality)

The referring party serves the referral within seven days of the notice of intention. From that referral, the Adjudicator has 28 days to issue a decision. The 28 can be extended:

by 14 days, with the referring party’s consent (so 42 days total),
by any further period, only with both parties’ agreement.

Most disputes of any complexity run to 42 days, not 28. Plan for 42.

Senior Representatives (NEC4)

NEC4 introduced a pre-adjudication step. Where the contract names Senior Representatives, a meeting of those representatives must be convened before W2 is invoked. Where that step is in the contract, skipping it can ground a jurisdictional challenge to the eventual referral. It is not a delay tactic; it is a circuit-breaker that resolves a meaningful share of disputes before a referral is needed.

Temporary finality

The Adjudicator’s decision is binding as a temporary final decision. It must be complied with immediately, even if a party intends to challenge it later in litigation or arbitration. “Pay now, argue later” is the operating principle of UK adjudication. Many disputes that pass through it never proceed onwards: compliance plus time tends to settle the matter.

Commercial implications

What it means on a live programme.

The 28-to-42-day decision window is where the work happens. The party referring has had time to prepare; the responding party has, effectively, a long weekend before they have to respond in substance. The asymmetry is brutal and underestimated. Contractors frequently refer near month-end when commercial teams are stretched thin; smart responding parties build a register of potential adjudications ahead of time and keep contemporaneous records that survive a one-week response cycle.

Enforcement of the decision happens in the Technology and Construction Court (TCC). Decisions are usually enforced by summary judgment within weeks. The grounds for resisting enforcement are narrow: jurisdictional challenges (the Adjudicator went outside their authority) and natural-justice breaches (one party didn’t get a fair hearing). Substantive disagreement with the Adjudicator’s reasoning is not a defence at the enforcement stage. Substantive disagreement is for the litigation that may, or may not, follow.

Failure modes

Where this fails in practice.

Notice of intention drafted as a generic letter that doesn’t actually identify the dispute. The Adjudicator can refuse jurisdiction if the dispute isn’t crystallised in the notice.
Referral that introduces new arguments not flagged in the notice. The Adjudicator may decline to consider them; the response only has to deal with the dispute as notified.
Adjudicator Nominating Body never reviewed at contract signature. The default body is then doing the selection, and outcomes vary materially by panel.
Senior Representatives step skipped where the contract requires it. The Adjudicator may decline jurisdiction on a procedural challenge.
Response prepared as if there is unlimited time. There isn’t. A response built in seven working days needs the records and the narrative ready to go.
Sitting on a clause 64 PM assessment. If the PM’s assessment under clause 64 is wrong, adjudication is the route. Silence makes the PM’s number the contract number.
Decision received and party simply doesn’t comply. TCC enforcement follows in weeks; non-compliance damages credibility for any subsequent dispute on the same programme.
Decision treated as final. The losing party loses the appetite to litigate after the dust settles, and a temporary-final number becomes the contract number by default.

Key points

What good looks like.

A standing “potential adjudication” log on every contract, naming the events that could escalate and the records each one would need. Maintained alongside the Early Warning Register, not separately.
A notice-of-intention template that names the dispute, the contract clause, and the relief sought. Three short paragraphs. Drafting it from scratch on the morning of issuance is how disputes are lost on form.
Senior Representatives meetings run with a real agenda, not as a formality. The meeting that resolves a dispute pre-adjudication saves both parties more than the legal cost.
Response capacity that can deliver a substantive defence in seven working days. That is a resource decision made before any dispute, not after.
Compliance with the Adjudicator’s decision treated as non-negotiable. Litigation strategy gets developed under a different timeline.
A 30-day post-decision review. Is the decision worth challenging in court? Most aren’t. Settling at temporary-final is often the right outcome, and recognising that early saves the legal cost of a litigation that was never going to land.

Practical takeaway

The discipline that compounds.

NEC adjudication under W2 is the UK construction industry’s primary dispute-resolution mechanism. It runs faster than most teams’ commercial cycles, and its outcome, even in its temporary-final form, usually sticks. The discipline that wins adjudications is the discipline of treating every potential dispute as if it might land in W2 with a seven-day response window. Teams that prepare for adjudication don’t usually need to fight one.

Future posts in this theme will go deeper on adjudication enforcement at the TCC, the practical mechanics of natural-justice challenges, and where W1 (the non-statutory NEC dispute path) still applies. Subscribe to get the next post the morning it ships.