NEC3 and the Specification for Highway Works

In a NEC3 Option A Contract the project is to to be constructed in accordance with the Specification for Highway Works which in the Preamble to the Specification has every Series of the Specification listed eg Series 400 Series 500 etc.etc. There is also the option to use a Prefix or Suffix such as an asterix A, S, C where the Clause has a National Alteration for one or more of the Overseeing Organisations of Scotland, Wales Northern Ireland.

My question is if the Client has failed to notify this change to the Specification in the Contract Documentation to the Regional Specification is it a Compensation Event as a change to the WI.

To clarify and this a hypothetical case as the real situation cocerns feature lighting. For example in the Specification for Highway Works Series 500 Drainage requires that if the Client equires a CCTV Survey it should be stated in Appendix 90/1 however in a particlar region of the UK the Regional Specification states that CCTV is mandatory to prove foul drains.

I only cite the above as an example the important question being the Client has made an omission in the Contract Documentation by not following normal convention so is that a Compensation Event

It’s difficult to answer this one without seeing in detail specifically what the documents state. Also it’s difficult to see what’s changed as if the specification is included in the Works Information and it states specific requirements apply in certain regions then it seem clear enough as to what is required unless I’m missing something?

Failure to notify a CE for a change to the Works Information does not prevent it from being a CE however if the Contractor wants to recover cost and time they will have to notify it themselves. The failure of the PM to notify only means that the CE is not caught by the 8 week time bar.


Thank you for the quick response and I will try to explain concisely

The Specification is included within the WI however within that Specification there is a mandatory requirement to specify if a regional alternative Specification is applicable to a specific project however this has not been done therefore I contend the original specification would be applicable because of this omission.

In practical terms the Specification in the Works information gives an alternative whether foul drains are proved by conventional purging methods OR alternately by CCTV survey however if the Client wants the CCTV option he must specify this in Series 500 Appendix 90/1. CCTV has not been specified therefore the contractor only has to price for conventional purging.

In the the Alternative Specification in this case “Sewers for Scotland” it states that a CCTV survey of foul drains is mandatory which is a substantial cost addition.

  1. On the first count in the Specification in the WI he has not asked for a CCTV in Appendix 90/1 therefore I would contend that to be a CE.

  2. On the second count he has omitted to change the requirement to use the Alternative Sewers for Scotland Specification therfore I contend that would be a CE as well.

The Clients counter argument is that because the job is based in Scotland the alternative specification would be applicable which in my opinion is not the case as this must be stated in the Contract Documents through the channels that I have stated above.

This situation would be applicable to any Form of Contract however in this instance it just happens to be an NEC3 Contract

if the Works Information does not make reference to the revisions (regional variances) then introduction of the revisions is a change to the Works Information and a CE.

the Contractor’s principal obligation is to provide the works in accordance with the Works Information so it is that document(s) that is relevant not the location of the works.


We are in total agreement in that situation that it would be a CE but if I could now add a slight twist.

Contained in the Contract Documents but not in Preamble to the Specifification ie the place where by convention any regional changes should be referenced against Series 500 Appendix 90/1 but it remains silent is the statement below which has obviusly been cut and pasted in and by the very wording “should be referenced” to my mind the Preamble to the Specification should have been changed.

K. Contractor’s Statutory Approval Requirements
K.2 Key Guidance & Legislation
*The following should be referenced in consideration of the detailed design and implementation of infrastructure works on the *******l development:

( Last item in a long list)

Sewers for Scotland, 3rd Edition, April 2015, Scottish Water

The above I should add is located in a rather obscure place in the Contract Documents not in the document headed up Works Information and the only way I found it was by carrying out a pdf filter search which I doubt if any Estimator would do when tendering a project. The estimator would only look at the Preamble to the Specification and if he did not find a regional change where it should be he would look no further.

I think the question I am asking this is a very obvious drafting mistake by the Client so is it still a CE

Probably an amiguity should have been raised earlier in the Contract but the reason it was not is because proving of foul is done in the defects period after the project is completed hence the matter did not raise its head until recently.

To my mind it is still a CE as by convention there are rules laid down and both parties should adhere to those rules and not issue misleading documentation