The NEC Supervisor checks that the works match what the contract requires. It carries out its tests and inspections, instructs searches for Defects, notifies Defects it finds and issues the Defects Certificate. It does not manage cost, time or change, which belong to the Project Manager.
The role appears in both the NEC3 and NEC4 Engineering and Construction Contract (ECC). Clause numbers here are for NEC4 ECC, with NEC3 in the table. For the wider picture, see who does what on an NEC contract.
What the Supervisor does
| Duty | NEC4 ECC | NEC3 ECC |
|---|---|---|
| Tell the Contractor before starting its own tests and inspections, and tell it the results | 41.3 | 40.3 |
| Watch any test the Contractor does, if it wants to | 41.3 | 40.3 |
| Do its tests without causing unnecessary delay | 41.5 | 40.5 |
| Tell the Contractor that Plant and Materials have passed a required pre-delivery test | 42.1 | 41.1 |
| Instruct a search for a Defect, with reasons | 43.1 | 42.1 |
| Notify each Defect it finds straight away | 43.2 | 42.2 |
| Issue the Defects Certificate | 44.3 | 43.3 |
The Scope (Works Information in NEC3) and the law set out which tests and inspections happen and who does each. If the Scope is thin, the Supervisor's work is thin too, so a Supervisor who wants a hold point should check that one is actually written in. The tests and inspections guide covers the mechanics.
What the Supervisor can't do
- Change the Scope. That power is the Project Manager's (14.3). A site comment asking for something better than the Scope requires isn't an instruction the Contractor can price, unless the Project Manager gives it.
- Accept a Defect. That decision is the Project Manager's, usually after a quotation (45.2).
- Assess the cost of a repeat test. The Project Manager assesses it and the Contractor pays (41.6).
- Tell the Contractor how to build. Quality checks concern the result, not the Contractor's method, unless the Scope says otherwise.
- Release the Contractor from responsibility. Passing a test or accepting a communication doesn't change the duty to Provide the Works (14.1).
Where a Supervisor's action costs money
Three compensation events depend directly on what the Supervisor does.
- 60.1(10): a search finds no Defect, unless the search was needed only because the Contractor gave too little notice of covering up a required test.
- 60.1(11): a test or inspection by the Supervisor causes unnecessary delay.
- 60.1(8): the Supervisor goes back on a decision already given to the Contractor.
A late reply from the Supervisor can also fall under 60.1(6). When its action causes an event, the Project Manager is the one who must notify it (61.1), which means the two roles need a working link. A search instruction the Project Manager never hears about is a compensation event no one has notified. See delay from tests and searching for Defects.
A worked example
A fictional water treatment job. The Supervisor reviews concrete test results and doubts one pour. It instructs the Contractor to core the slab, stating that two cubes fell below the Scope's strength. The coring costs an illustrative £6,000 and takes two days.
| Result | What follows |
|---|---|
| Cores pass | Compensation event, 60.1(10). The Project Manager notifies it and instructs quotations. The Prices and possibly the Completion Date change. |
| Cores fail | A Defect. The Supervisor notifies it, the Contractor corrects it within the defect correction period and bears its own cost. |
Before instructing a search, the Supervisor should record its reasons and tell the Project Manager, so the budget risk is known. Being over-cautious has a price, but a real doubt about structural work usually justifies it.
The Defects Certificate
The Supervisor issues the certificate at the end of the defects process. If nothing is outstanding it comes at the defects date; if notified Defects remain, the timing depends on how they are dealt with and on the last defect correction period. It lists any Defects not corrected, or says there are none. Issue it on time, because the final assessment follows it. The Defects Certificate guide has more.
Working practice
- Read the Scope for tests, hold points and who does what. Raise gaps early, through the Project Manager.
- Agree the notice arrangements for covering work and write them in the quality records.
- Keep notifications separate from other communications (13.7). A Defect buried in a meeting note is a poor record.
- Notify the Contractor of any delegates, such as resident inspectors, and the actions each may take (14.2).
- Use a Defect register shared with the Project Manager, and meet regularly.
Related guides
- NEC Roles: Who Does What on an NEC Contract
- The Supervisor Under NEC4
- The Contractor's Duties Under NEC
- The Client's Role Under NEC
- The NEC Project Manager
- NEC Project Manager Responsibilities Checklist
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This guide is general information in our own words, not legal advice. Your contract and its Contract Data always govern. NEC, NEC3 and NEC4 are trade marks of Thomas Telford Ltd; Contract Status is not affiliated with or endorsed by NEC.