Contingency sum
Published:
28 October 2020
Edited:
17 August 2025
A contingency sum is an amount of money, usually expressed as a percentage, included in the project budget to allow for the unknown or unresolved aspects of a design. It is usual for the initial allowance to be as much as 25% to 30%. This would be reduced as the design develops and is more resolved. By the time that construction starts the percentage may be as little as 3% to 5% of the contract price.
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