NEC3 Option B - BoQ Undermeasure

Hello,
Currently working on an NEC3 Option B project. We (main contractor) realised that no 215mm internal walls have been measured, of which there are 1,000’s of m2. CE was notified accordingly, no impact on the completion date - works were facilitated by providing extra brick-layers and extra resources (telehandler, crane, scaffold etc.)
Costs for the CE have been issued to the PM and where based on using a BoQ rate for external 215mm walls and associated preliminaries, the aforementioned resources.
The PM is accepting the costs for the works but is refusing to pay any additional preliminary costs that enabled the extra works to take place. BoQ rate for the actual building work is very low and as a result of his assessment we are losing even more money on this element of works.
Looks like we will be proceeding to adjudication and any feedback would be great!
Thanks.

Shaun,

You need to check (and let the PM know accordingly) that the event qualifies as a CE under cl. 60.4, i.e.:

i) the difference in the quantity was not a result of a change in the WI (it sounds like it wasn’t);

ii) the difference causes the Defined Cost per unit of quantity to change (definitely from what you say); and

iii) the changed quantity results in the BoQ sum to be more the 0.5% of the tendered total of the Prices.

If the three above tests are satisfied, the CE should be assessed in accordance with cl. 63.13, probably as a lump sum (3rd bullet point) if the work was already done.