Variation Order / Change Order

A variation order (also called a change order) is a formal written instruction issued by the engineer or employer that modifies the scope, specification, or sequence of work under an existing contract, with corresponding adjustments to the contract price and completion time determined through the contract's valuation and entitlement provisions.

What is a Variation Order / Change Order?

Variations are an inevitable feature of construction and supply contracts. No design or specification survives contact with site conditions or evolving client requirements without some adjustment. Under FIDIC and World Bank standard contract forms, only the engineer has authority to instruct a variation; the contractor cannot assume that a verbal instruction or a design change creates a valid variation without a written order. The engineer issues the instruction, and the parties then agree or determine the value of the varied work at applicable contract rates, at negotiated rates for new work items, or at day-works rates where measurement is impractical. If the variation affects the programme, the contractor is also entitled to an extension of time, which reduces exposure to liquidated-damages.

Variation orders interact directly with the contract price: the total contract value after all variations determines the base for retention, percentage-based fees, and bond amounts. A contract with a high volume of variations is administratively intensive and should prompt the employer to consider whether the original design was adequately developed before procurement.

Why Variation Order matters for bidders

The variation mechanism is one of the most important financial and legal provisions in any contract. Contractors that fail to give timely notice of their entitlement to additional time or money for a variation, as required by the contract conditions, frequently lose that entitlement even when it is substantively justified. Read the notice period requirements carefully and apply them strictly. Maintain a variation register from day one: every potential variation should be identified, priced provisionally, and tracked. When an instruction arrives that changes scope without a formal variation order, request the written instruction immediately. Acting on verbal instructions without written authority puts the contractor's cost recovery at risk.

FAQ

Can the employer instruct a variation that reduces the contract scope?

Yes. Omission of work is a valid type of variation, but the employer cannot use an omission variation to give the work to another contractor. If the omitted work is later re-awarded separately, the original contractor may have a damages claim.

What happens if the contractor disagrees with the engineer's valuation of a variation?

The contractor can dispute the valuation through the contract's claims-and-disputes mechanism, but must continue performing the varied work while the dispute is resolved.

Is there a limit on the value of variations that can be instructed?

Standard contracts do not set a hard cap, but MDB-financed contracts may require re-tendering or a no-objection from the bank if the total of variations exceeds a significant percentage, commonly 15 to 20 percent, of the original contract price.