Variations: Establishing Entitlement, Handling Directions, and Getting the Valuation Right

No head of claim generates more contested money on Australian projects than variations — and no area relies more heavily on assumptions that the case law keeps disturbing. The latest disturbance is significant: in late 2025 the New South Wales Court of Appeal held that variations directed, priced and paid during a project remained open to reassessment at final account, because the contract made all payments before the final payment "on account" only. If your variation register shows "approved" next to a value, that word may mean less than you think.

Entitlement: the direction is the foundation

Under the standard machinery — AS 4000's clause 36 is the archetype — the superintendent directs variations (additions, omissions, changes in character or quality), and the contractor must not vary the work without a written direction. Three recurrent entitlement problems sit around that simple structure:

Oral directions. Work directed orally and performed sits outside the formal machinery, but it is not unrecoverable. The High Court's Liebe v Molloy (1906) 4 CLR 347 line holds that where the owner knows extra work is being performed, knows it is outside the contract, and knows the builder expects payment, a promise to pay can be implied despite a writing clause. Update Constructions Pty Ltd v Rozelle Child Care Centre Ltd (1990) 20 NSWLR 251 puts the modern footing in restitution — and adds that a principal whose own conduct induced non-compliance with formal requirements may be estopped from relying on them. These are rescue doctrines, though: expensive, uncertain and fact-hungry. The operational answer is the contract's own tool — under AS 4000, a contractor can require written confirmation of an oral direction (cl 20); the standing site rule should be confirmation of every oral instruction within 24 hours.

Scope versus variation. Whether work is "extra" at all is a construction question the records must answer — drawings, specification, the contractual design obligations (acute on design and construct contracts, where design development is usually the contractor's risk). And the variations power has outer limits in both directions: it is not a power to transform the project into something manifestly different (Wegan Constructions Pty Ltd v Wodonga Sewerage Authority [1978] VR 67, where a directed "variation" producing a manifestly larger project — excavation up 60 per cent, sewer length up 40 per cent — was held outside the power), nor a power to omit work in order to hand it to another contractor (Commissioner for Main Roads v Reed & Stuart Pty Ltd (1974) 131 CLR 378).

Notice interaction. Variation entitlement increasingly arrives wrapped in time bars — claims to be notified under the general claims clause within fixed periods. Everything we have written about notice discipline applies here with full force.

Valuation: the order of precedence, and the new warning

AS 4000 cl 36.4 prices variations in a fixed order: prior agreement; applicable contract rates; rates in a priced bill or schedule to the extent reasonable; and finally reasonable rates and prices including a reasonable amount for profit and overheads. The discipline the order implies — agree the price before the work where possible — remains the single most valuable variation habit on either side of the contract.

Then comes the warning. At first instance in Calibre Construction Group Pty Ltd v Kaloriziko Pty Ltd (No 2) [2025] NSWSC 593, the court held that variations directed and valued by the superintendent under an amended AS 4902 were finally priced — the "on account" language governed progress payments, not variation pricing. The Court of Appeal reversed: Kaloriziko Pty Ltd v Calibre Construction Group Pty Ltd (No 2) [2025] NSWCA 259 held that where the contract provides that all payments other than the final payment are "on account" only, even approved and paid variation values remain provisional and can be reassessed up to final entitlement — a holding that stripped millions from the builder's recovery. The practical consequence runs both ways: contractors cannot treat an approved variation as banked until final certificate (or until the contract expressly makes variation pricing binding), and principals retain more final-account leverage than the industry assumed.

What this means in practice

1. Run the variation register as an entitlement document. Every direction (written and oral-confirmed), its scope basis, pricing status under the cl 36.4 hierarchy, approval status — and now a column for finality: is this value binding, or "on account"? After Kaloriziko, that column is real money.
2. Price before performance, and seek finality wording. Pre-agreement under cl 36.4(a) avoids the valuation fight; an express term that agreed variation values are final and binding (not "on account") avoids the Kaloriziko fight. Negotiate it into the amendments, or at least into individual variation agreements for significant items.
3. Never rely on the rescue doctrines by choice. Liebe v Molloy and Update Constructions exist for the breakdown cases. The 24-hour written-confirmation habit, the cl 20 confirmation demand, and the notice register make them unnecessary — and they are the difference between contractual entitlement and a restitution claim with an estoppel argument attached.
4. Substantiate like it's a claim, because it is. Each variation file: the direction, the scope analysis (why this is extra), the build-up (quantities, rates, time-related components stated separately to avoid prolongation double-recovery), and contemporaneous cost capture for daywork-style items.
5. Watch the omissions. A principal omitting work to give it elsewhere is in Reed & Stuart territory; a contractor watching scope migrate to others should say so in writing immediately — the breach is in the redirection, and silence reads as acquiescence.

Key takeaways

• The direction — written, or oral-confirmed fast — is the foundation of variation entitlement; the rescue doctrines (Liebe v Molloy, Update Constructions) are last resorts.
• The variations power has limits: no transformation of the project (Wegan), no omitting work to hand it to others (Reed & Stuart).
• Valuation follows the cl 36.4 hierarchy; agree prices before performance wherever possible.
• Kaloriziko v Calibre [2025] NSWCA 259: under "on account" payment wording, approved and even paid variation values can be reopened at final account — seek express finality wording, and don't bank approvals.

This article is general information only and is not legal advice. For advice on a specific contract or dispute, seek legal counsel or contact Sumit Consulting for commercial and claims advisory support.