NEC ECS: Scope Definition

We are in an NEC ECS Option A Contract which has a clearly defined Works Information and a set of drawings. The Works information lists out (bullet points) what works are to be undertaken by us (Subcontractor), and what works to be undertaken by the Contractor.

However, the set of drawings (Site information) contains ‘other’ works that are not listed within the Works Information.

The Contractor has assumed all works shown within the drawings are to be undertaken by the Subcontractor, but the Subcontractor believe they are to only undertake the works listed within the Works Information, and use the Drawings as a reference on how to undertake said works. Note under the bullet points of work items listed within the WI it references the drawings relevant to the items of scope.

Is it correct to assume the Subcontractor is correct and should be working to the list within the WI? My assumption is yes.

Unfortunately, a lack of precision (probably due to a lack of understanding) of what is Works Information and what is Site Information and hence specifying/referencing it correctly is quite common and this seems to a variant of that issue !

From what you say, I believe your assumption is correct.