NEC3 Option B, Clause 60.7

Our drawings indicate concrete grade 40/20 shall be used. However, only an item of concrete grade 30/20 is provided in the BoQ. The Project Manager subsequently issued a PMI to clarify the Works Information that concrete 30/20 should be used.

According to ECC Clause 60.7, in assessing a compensation event which results from a correction of an inconsistency between the Bill of Quantities and another document, the Contractor is assumed to have taken the Bill of Quantities as correct.

In assessing the above case, concrete grade 30/20 is confirmed to be used as BoQ item. Should the works be measured under the BoQ item and the Prices is not to be changed?

In short, the Prices should be changed to reflect the difference in defined cost between the BoQ item 30/20 and the Works Information requirements for 40/20.
The Contractor is deemed to have assumed that the BoQ is correct under 60.7, if the WI requires something different the Contractor is entitled to the difference between the BoQ and the WI.

The PM’s instruction changing the WI resolves the ambiguity between the WI and the BoQ and triggers a CE under 60.1(1) which the PM is obliged to notify to the Contractor under clause 61.1 and also instruct it to submit a quotation. You should also note that under clause 63.8, a change to the Works Information in order to resolve an ambiguity is read in favour of the party that did not provide the Works Information. Clause 60.7 sets the starting point for making any subsequent assessment as the Contractor is assumed to have taken the BoQ as correct, so clearly in the scenario you describe the the Prices will not be reduced, even though the mix in the WI might be more expensive than the mix stated in the BoQ. The Prices can be changed to higher prices if the Contractor forecasts a time and cost increase as a result of the CE but that will need to be demonstrated within its quotation.
It is important under Option B to change the Prices in accordance with clause 63.13 so that the PWDD operates correctly, if there is no change then the PWDD will be based on the actual quantity of work completed multiplied by the rate for the original BoQ item, if there is a change then the BoQ must be changed and the PWDD will be based on the new changed item.


Very clear explanation, thank you