Nothing before this certificate was acceptance.

The period runs on notices, not on defects

The obligation is to remedy defects notified on or before the expiry date of the period — and the notice, not the defect, is what the clause keys on.

Which puts the emphasis somewhere other than where people expect. A defect present throughout the period and noticed a week late falls outside the clause, however real it is. A defect noticed on the final day falls inside it.

That asymmetry cuts towards whichever party is paying attention. An employer who inspects properly in the closing weeks catches things; a contractor who knows the expiry dates knows when the exposure stops growing.

So the period is a notification window rather than a warranty of soundness, and both parties are running a clock against a document trail rather than against the condition of the works.

That is worth understanding before it is used against you and before you fail to use it.

It stretches, with a ceiling

The period isn't fixed. The employer may extend it where the works, a section, a part or a major item of plant can't be used for its intended purpose because of a defect the contractor is responsible for.

Two things about that. The test is use again — the same measure that decided the rejection thresholds in week 30 and what could sit on the list in week 31. Across the whole of this phase the contract keeps asking one question in different places, and it is never about whether the work is good.

And the elasticity has a limit: the period can't be extended by more than two years beyond what the contract stated. So the exposure is bounded, which is worth knowing when somebody describes an extension as open-ended.

A bounded exposure is also a plannable one. Two years past the stated expiry is a date you can calculate on the day of handover, and it is the outer edge of the obligation whatever else happens in between.

The extension is also per item rather than across the board. A period stretched because one pump could not be used runs on for that pump, which is how a project ends up with several expiry dates it never intended to create.

Fail to remedy and you pay for work you don't own

Where remedying is unduly delayed, the employer can fix a date by notice, allowing reasonable time. Miss it, and at their sole discretion they may have the work done by others at the contractor's cost.

The clause then adds something people miss on a first reading: the contractor has no responsibility for that work.

Read as an allocation it is coherent. Nobody can be answerable for the quality of work they neither did nor supervised. Read as a position it is unusual: you are paying for an outcome you no longer own, performed by somebody you didn't choose, on a plant that carries your name.

Which makes the fixed date in that notice one of the more consequential dates left in the project, and one that arrives with reasonable time attached rather than a fixed period.

Reasonable is the word to attend to. It is decided against the circumstances, so what the notice allows depends on the item, the access, the lead time on a part, and whether anybody said so at the time. A date accepted without comment is a date agreed.

The certificate that is acceptance

The Performance Certificate issues within four weeks of the latest of the expiry dates — or as soon after that as the contractor has supplied the documents and completed and tested everything, including remedying defects.

The word latest is doing work, and week 32 is why. Take over four parts on four dates and there are four periods; the certificate waits for the last of them.

One slow part holds the acceptance of everything.

And an extension moves it again. A period stretched because one item could not be used pushes the latest expiry, which pushes the acceptance of a works that has otherwise been finished and operating for two years.

And there is a deeming here too, pointing the other way from week 31's. Where the Engineer fails to issue it, the certificate is deemed issued four weeks after the date it should have been — which is later than the deadline, not earlier. Silence at taking over gave you time. Silence here costs you a month.

And the contract stays in force

The last thing is the one that undoes the sense of an ending.

After the certificate, each party remains liable for any obligation still unperformed — and for working out what those are, the contract is treated as remaining in force. There is a long-stop for plant defects at two years past the expiry, and exceptions for fraud and deliberate default, but the general position is that the document doesn't switch off.

So the Performance Certificate is acceptance and it isn't termination. It closes the defects mechanism and leaves the contract standing behind whatever else was promised, which is why the records this track has asked for keep mattering after the last certificate is filed.

It also settles a question worth asking once. People speak of a project ending, and the phase has produced four candidates for the moment it does: the last pour, the taking-over date, the expiry of the periods, the Performance Certificate. None of them is it. What ends is the mechanism for making somebody come back and fix things.

Which has a practical consequence for the records. A file closed on the day the certificate arrives is a file closed while the document behind it is still operative, and the last person to touch it is the one deciding, without being asked, what the organisation keeps.

System design

Row two is a derived figure and nothing on a project recalculates it. The latest expiry changes every time a part is taken over or a period extends, and the date the whole contract closes from moves with it — silently, since nothing recalculates it.

Record	Produced by	Required quality	Verified against	Feeds
Expiry sheet	You, from the first certificate	One line per period, with what it covers and when it ends	Each taking-over certificate	When acceptance can happen at all
Latest expiry	The sheet, recalculated	Redone whenever a part is taken over or a period extends	The sheet it comes from	The date the Performance Certificate runs from
Certificate due and deemed dates	You, from the latest expiry	Both dates, since the deeming lands a month after the deadline	The latest expiry	Whether to wait or to ask
Defect notices received	The employer, throughout	Held with their receipt dates, in one place, for the whole period	Your correspondence file	Whether an obligation bit at all
Extensions claimed	The employer, per claim	Records the use that could not be had, since that is the test	The intended purpose of the thing	How long the exposure runs

Row four is a filing instruction rather than a record, and it is here because the clause turns on receipt dates. A defect notice in somebody’s inbox with the others is evidence; the same notice in a project mailbox is a search.

Practical insight

Keep your own one-page expiry sheet from the first taking-over certificate onwards.

Every period you are inside: what it covers, the date it started, the date it expires, and whether an extension has been claimed against it. Then one line at the bottom — your latest expiry of the lot — because that single date is what your Performance Certificate counts from, and it moves every time a part is taken over or a period is extended.

From your bottom line, calculate two more: the day your certificate is due, and the day it would be deemed issued if nobody acts. Diary both. Your second date is a month later than the first, and knowing that in advance is the difference between waiting and asking.

And keep every defect notice with the date you received it, in one place, for the whole period. Whether an obligation bit at all turns on whether that notice arrived before an expiry date — a question about your correspondence file rather than about the works, and one you answer in an afternoon or not at all.

Key takeaways

• The contractor’s obligations aren't treated as performed until the Performance Certificate issues, and only that certificate counts as acceptance.
• The taking-over certificate transferred possession, care, risk and a set of clocks, and accepted nothing.
• The obligation is to remedy defects notified on or before the expiry date, so the period is a notification window.
• A defect that existed throughout and was noticed a week late hasn't been caught, however real it is.
• The employer may extend the period where something can't be used for its intended purpose because of a defect the contractor is responsible for.
• That is the use test again, which this phase has now applied at rejection, at certification and at extension.
• The extension is capped at two years beyond the stated period, so the exposure is bounded rather than open-ended.
• Where remedying is unduly delayed the employer may fix a date and, on failure, have the work done by others at the contractor’s cost.
• The contractor has no responsibility for that work, so it is paid for by somebody who no longer owns the outcome.
• The Performance Certificate follows the latest of the expiry dates, so one slow part holds the acceptance of everything.
• If the Engineer fails to issue it, it is deemed issued a month after it was due — a deeming that lands late rather than early.
• After the certificate each party stays liable for unperformed obligations, and the contract is treated as remaining in force to determine them.

Records born here. The expiry sheet, one line per period · the latest expiry, recalculated whenever a part or an extension changes it · the date the Performance Certificate is due, and the date it would be deemed · every defect notice with the date it was received · every extension claimed, and the use it was based on · any date fixed for remedying, and what followed.

What is coming next

Phase F ends here. The works are accepted, and the site still has your equipment on it.

What follows the certificate is a short list of physical obligations with a deadline attached, and a consequence for missing it that is unlike anything else in the contract: the employer may sell what you leave behind.