New Wembley Result: EOT Clauses 2, Time At Large 0

The new Wembley stadium has so far generated seven interesting court judgments. The most important so far for the industry was given last week. It is the first case for years on a golden rule and its avoidance:

• A party to a contract generally cannot insist upon the performance of an obligation which he has prevented the other party from performing (the prevention principle). In construction that means an employer, say, cannot hold his contractor to a specified completion date if the employer prevents the contractor from completing by that date. Instead the time for completion becomes "at large" (that is, the contractor must complete within a reasonable time).

• Often the contractor is required to pay liquidated damages (LDs) to the employer for late completion of his works. However he is not when the time for completion becomes at large (as there is no specified date from which the LDs can run) and the employer is left to claim general damages.