Uniform Building Contractors Ltd v The Water and Sewerage Authority of Trinidad and Tobago (Trinidad and Tobago)

Under a design-and-build lump-sum contract, work is not a variation merely because it is more onerous or was treated as such by the engineer. The question is whether the work falls within the contractual Employer’s Requirements or Works, expressly or impliedly, and was included in the lump sum. Contractual variation procedures and notice provisions must then be followed. A clause stating that failure to give notice within 28 days removes entitlement to additional payment is a condition precedent where the clause links compliance to payment. Termination operates prospectively and cannot revive an accrued contractual claim. Waiver or estoppel requires a properly pleaded case and clear evidence of an unequivocal representation, reliance and detriment. An engineer cannot waive or amend contractual obligations where the contract expressly limits that authority.

The appeal concerned a pipelaying contract between Uniform Building Contractors Ltd and the Water and Sewerage Authority of Trinidad and Tobago. The contract used the FIDIC Yellow Book 1999 form and was a fixed-price, design-and-build contract.

The High Court dismissed UBC’s claim and WASA’s counterclaim. The Court of Appeal allowed UBC’s appeal in respect of four claimed items: roadway excavation, disposal of unsuitable material, imported backfill and night work. The central issues were whether those items were contractual variations, whether UBC’s procedural failures barred recovery, and whether waiver or estoppel could be relied upon.

1. Appeal allowed. The Board reversed the Court of Appeal’s decision and dismissed UBC’s claim. It was unnecessary to determine the separate issues of causation and quantum.
2. The ordinary restraint on appellate interference with factual findings did not prevent the Court of Appeal from reconsidering the issues. The trial judge’s findings were negligible and did not explain how the contract covered the disputed work. The Court of Appeal was therefore entitled to consider the issues for itself. Its own reasoning was nevertheless flawed because it did not analyse the contract terms, treated the engineer’s conduct inconsistently, and introduced waiver and estoppel without pleadings or evidence.
3. Whether work is a variation is primarily a question of contractual construction. In a lump-sum contract, an underestimate of work required to meet the contractual requirements is not a variation if the work was expressly or impliedly included in the lump sum. The roadway cutting and excavation, disposal of unsuitable material, importation of backfill and consequential night work were all within UBC’s contractual obligations. The engineer’s opinion could not displace that conclusion.
4. The FIDIC procedures were also decisive. A contractor seeking additional payment had to notify likely cost increases, pursue the variation procedure and obtain an engineer’s determination. Clause 20.1 required notice within 28 days and stated that failure resulted in no entitlement to additional payment and discharged the employer from liability. Applying the principles in Tata Consultancy Services Ltd v Disclosure and Barring Service [2025] EWCA Civ 380, Bremer Handelsgesellschaft mbH v Vanden Avenne-Izegem PVBA [1978] 2 Lloyd’s Rep 109 and Scottish Power UK plc v BP Exploration Operating Co Ltd [2015] EWHC 2658 (Comm), clause 20.1 was a condition precedent. UBC’s failure to comply was fatal.
5. Termination operated prospectively and did not revive claims already lost through non-compliance. Waiver and estoppel were unavailable because they had not been pleaded or evidenced, and the engineer lacked authority under clause 3.1 to amend the contract or relieve UBC of its obligations. Only the contracting parties or an authorised representative of WASA could do so.

1. Privy Council: Reversed the Court of Appeal and dismissed UBC’s claim.
2. Court of Appeal of the Republic of Trinidad and Tobago: On 24 November 2023, allowed UBC’s appeal and awarded TT$13,915,215.46, with interest and costs.
3. High Court: On 17 February 2017, dismissed UBC’s claim and WASA’s counterclaim.