This Practice Note examines the circumstances in which a construction contract might entitle a contractor to claim additional time in which to complete the works (known as an 'Extension of time' or 'EOT'), and the importance of contractual procedures in this regard.

A construction contract will, ordinarily, specify the date by which Practical Completion of the works must be achieved (see Practice Note: What is practical completion?). This is typically referred to as the 'Completion date' (or something similar). However, during the course of a construction project, it is common for events to occur which delay (or threaten to delay) the progress of the works, affecting the critical path (see Q&A: What is the critical path?) and having an impact on the contractor’s ability to complete the works by the completion date. These are often referred to as 'delay events'. An extension of time allows the contractor to complete its works within a set period after the original contractual completion date, without becoming liable to pay the employer liquidated damages (or, where there is no provision