Under an NEC Engineering and Construct Contract, which works does a Contractor design?

  • All of the works
  • None of the works
  • Works he's instructed to design
  • The design stated in the Scope

I hope everyone is enjoying our NEC trivia! Well done to those who answered correctly – a Contractor designs the parts of the works which the Scope (or Works Information in NEC3) says they are to design (clause 21.1).

Design obligation

The ECC can be used like a traditional contract where the works are designed by the Employer and the Contractor is only responsible for constructing the works; or the Contractor could be responsible for both the design and build.

Things are often somewhere in the middle, where the Employer may have carried out some preliminary design which is then to be completed by the Contractor. The interface between these parts of the works should be carefully thought through.

An important element with any design obligation is the standard which the design is to meet, whether that is fitness for purpose or reasonable skill and care. By default, NEC ECC imposes a fitness for purpose type obligation where strict compliance with the Scope is required and the Scope will often state the purpose of the design. Option X15 is then often selected which imposes an obligation on the Contractor to use reasonable skill and care in preparing the design. This is however a complex area and there is the possibility of parallel obligations for both reasonable skill and care and fitness for purpose being created so care needs to be taken in clarifying the extent of the design obligation.

Acceptance of design

Another important element is submission and acceptance of the design. The Scope will specify what parts of the Contractor's design must be submitted to the Project Manager for acceptance. The time limits for the Project Manager to respond are set out in clause 13. The period for reply is generally quite short and so, if additional time to review the design is needed, appropriate amendments should be made.

Acceptance of the design does not change the Contractor's liability for that design (clause 14.1). Once accepted, the Contractor must construct the works in accordance with the accepted design ensuring compliance with the Scope.

If the Project Manager rejects the design, they must state one of the two reasons which are: that it does not comply with (1) the Scope or (2) the applicable law. If acceptance is withheld for any other reason that constitutes a Compensation Event under Clause 60.1.