Prolongation in construction contracts
The term ‘prolongation’ refers to the extra costs that a contractor may incur as a result of the completion of the works being delayed by an event that is the responsibility of the client. Such events might include; failing to give the contractor possession of the site on the date specified in the contract; delays in giving instructions and so on. The contractor may incur additional costs as a result of having to remain on site for longer than anticipated, for example, additional labour costs, plant costs, off-site overheads, fluctuations and so on.
Prolongation is sometimes described as being synonymous with ‘loss and expense’ however, this is incorrect. Loss and expense is a wider term that refers to matters which are the responsibility of the client that materially affect the progress of the works. This includes matters that disrupt, rather than delay the progress of the works, but still entitle the contractor to make a claim for additional costs incurred. Claims for disruption result from the additional cost of adopting inefficient working methods as a result of the disruption.
Generally prolongation is easier to prove than disruption.
For more information see: Loss and expense.
 Related articles on Designing Buildings Wiki
- Concurrent delay.
- Consequential loss.
- Extension of time.
- Force majeure.
- Liquidated damages.
- Loss and expense.
- Profit and overheads.
- Programme consultant.
- Relevant event.
 External references
- Isurv. Loss and expense claims.
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