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Last edited 14 Aug 2018
Payment for extra work
Building works are complex, and it is common for a contractor to carry out works not described in the original contract documents for which they consider they are entitled to additional payment over and above the original contract sum. However, the fact that a contractor has carried out extra work does not automatically mean they have a right to payment for it.
- The contract sum does not include the additional work.
- There was an express or implied promise to compensate the contractor for the work.
- The work was instructed by an authorised agent.
- Any conditions precedent to payment, as imposed by the contract, have been fulfilled.
For example, where the contractor has carried out extra work or uses superior materials to those specified, but they have not been instructed to do so, this will not entitle them to extra payment. Similarly, if the employer agrees to different work, they will not necessarily be liable for any additional payment if they were not informed of the increased costs involved.
Generally, in an emergency situation where a contractor pays a sum to preserve the employer’s property, and has not been possible to obtain instructions from the employer, the contractor will be entitled to additional payment.
If the employer refuses to provide additional payment for extra work, the contractor may refuse to carry out the work. If the employer promises the additional payment, and it later transpires that the work is included in the original contract sum and so is not ‘extra’, the promise to pay will generally not be binding.
Typically, contracts provide for changes to the works described in the contract documents through variation clauses. A variation (sometimes referred to as a variation instruction, variation order or change order) is an alteration to the scope of works in the form of an addition, substitution or omission from the original scope of works. Variations may also be deemed to occur if the contract documents do not properly describe the works actually required.
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