What is an Extension of Time (EOT) claim in construction?
An Extension of Time (EOT) claim is a contractor’s formal request for more time to complete works when a delay outside its control affects the completion date. A valid EOT links the delay event to its cause, the programme impact, the entitlement clause, and supporting records.
In construction contracts, an Extension of Time claim asks the employer to move the contractual completion date because a qualifying delay — one the contract says the contractor is entitled to claim for — has pushed the works out. Granting an EOT protects the contractor from liquidated damages for that period and may open the door to prolongation cost.
A defensible EOT typically has to demonstrate:
- the cause (e.g. a late instruction, a variation, unforeseen ground conditions)
- notice that it was raised in time (often via the RFI trail)
- the schedule impact, shown against the accepted programme
- the contract clause that grants the entitlement
- the records that substantiate all of the above
Assembling that evidence by hand across the schedule, the RFI system, the contract documents and the cost ledger is slow and error-prone. Bildstak’s Claims Builder traces the chain from cause to quantum across those sources and assembles a cited claim package, which is what turns a dispute into a documented entitlement.
Updated 2026-06-19