NEC clause 36 lets the Parties agree to bring the Completion Date forward. It works by quotation: a price and a revised programme are prepared, and the Completion Date moves only if the quotation is accepted. Nobody can impose acceleration, and a Contractor that speeds up without a quotation doesn't get an earlier Completion Date or a price for doing so through this clause.
NEC4 ECC changed how the process starts, so the edition matters. This page covers both editions. It is part of the NEC programme guide.
NEC3 and NEC4 compared
| Step | NEC3 ECC | NEC4 ECC |
|---|---|---|
| Who starts it | The Project Manager instructs a quotation (36.1) | Either the Contractor or the Project Manager proposes it (36.1) |
| Next step | The Contractor either quotes or explains why it won't, within the period for reply (36.2) | If both are prepared to consider it, the Project Manager instructs a quotation |
| If the Contractor doesn't want to | It explains why, and nothing more follows | It isn't prepared to consider it, so no instruction follows |
| Quotation | Prices, revised programme with the earlier Completion Date and changed Key Dates, plus assessment details | The same content (36.2) |
| Acceptance | Changes the dates and the Prices or forecast, depending on the main Option, and the revised programme is accepted | Changes the Prices, Completion Date and Key Dates, and the revised programme is accepted (36.3) |
Time limits differ by form, so check yours. Under NEC4 ECS, the Subcontractor quotes within two weeks of the instruction and the Contractor replies within four. Published commentary on the NEC4 ECC gives up to three weeks for the quotation and three weeks for the reply, so don't assume the ECS figures carry across. Confirm them in clause 36 of your own contract.
What isn't acceleration
- The Contractor's own recovery. If it adds resources to recover its own delay, the Completion Date doesn't move, and there's no payment through this route. Recovery measures belong on the revised programme (32.1).
- Finishing early. A Contractor can plan and reach Completion before the Completion Date, leaving terminal float. That doesn't move the date. See terminal float.
- An instruction. The Project Manager's power to change things under 14.3 reaches the Scope and Key Dates, not the Completion Date. So an earlier Completion Date can't simply be instructed.
Worked example: pricing an acceleration
A fictional bridge refurbishment, with illustrative figures. The Client wants to open four weeks early, before a major event. The current Completion Date is 26 September, and planned Completion is 19 September.
| Item | Effect | Amount |
|---|---|---|
| Second shift on deck works, ten weeks | Additional people and Equipment | £118,000 |
| Longer traffic management at night | Additional cost | £21,000 |
| Earlier delivery surcharge on bearings | Additional cost | £9,000 |
| Shorter time on site | Reduced time-related cost | (£15,000) |
| Risk allowance for working closer to limits, and Fee | Risk and Fee | £22,000 |
| Quotation | New Completion Date: 29 August | £155,000 |
Notice the float. The Contractor's programme had a one-week gap before the Completion Date, and this quotation keeps it, with planned Completion moving to 22 August. Client and Contractor can trade the end date, the price and the float in discussion. Clause 36 gives no formula for the price, so it is a commercial negotiation.
Practical points
- Start with a talk. Clause 36 asks for a quotation, and a quotation costs money to prepare. Check the appetite first.
- Be precise. State the target date and which Key Dates should change.
- Check the secondary Options. Delay damages under X7 run from the new date once it's accepted, and a bonus under X6 is measured to it, so the new date raises the stakes for the Contractor.
- Read your main Option under NEC3. What changes on acceptance sits in the Option clauses: the Prices at 36.3 under Options A to D, and the forecast of total Defined Cost at 36.4 under Options E and F.
What happens if the quotation is refused?
Under NEC4 ECS, the reply says either that the quotation is accepted or that it isn't, with the dates unchanged. Refusing an acceleration quotation doesn't fall within 60.1(9), which specifically leaves it out, so the Contractor shouldn't plan on recovering its preparation cost under that heading. For more on how instructions work, read about Project Manager instructions.
Related guides
- The NEC Programme: A Complete Guide
- Using the Programme to Assess Compensation Events
- NEC Programme Review Checklist
- An NEC Guide for Planners
- Sectional Completion
- Access Dates and Starting Work
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