Time bars and notice traps: how subbies lose money they've earned

The most expensive clause in your subcontract isn't the liquidated damages rate or the indemnity. It's the sentence that says a claim is barred unless written notice is given within some number of days — because that sentence doesn't cost you money when something goes wrong on site. It costs you money when the paperwork is three days late, which is a much more common event.

Standard forms are relatively civilised about this: AS4000 gives 28 days for an extension-of-time claim. Aggressive subcontracts cut that to 7 days, or 5, or 48 hours — and then layer a second and third notice requirement behind the first, so there are more tripwires than anyone on site is tracking. Here's how the trap works, and the discipline that beats it.

How a time bar actually operates

A time bar makes notice a condition precedent to the claim. Miss the window and the entitlement is extinguished — not weakened, not discounted for lateness: gone. The merit of the underlying claim is irrelevant. You can be provably entitled to six weeks of extension for a delay the head contractor caused, and lose all of it because your notice landed on day 8 of a 7-day window.

Courts in the markets we cover generally enforce clear time bars precisely because they're clear. Judges don't enjoy the results, but "the parties agreed notice was a condition" is an argument that wins. Plan on the bar being enforced as written.

The layered trap

Modern aggressive drafting doesn't use one time bar — it stacks them:

1. Initial notice within days of the event ("the Subcontractor shall give notice within 5 business days of the circumstance first arising").
2. Detailed particulars within a second window ("full particulars including causation and quantum within 10 business days of the notice").
3. Ongoing updates ("updated particulars every 28 days while the delay continues").

Miss any layer and the claim dies. Count the distinct notice obligations in your next subcontract — variations, EOT, latent conditions, acceleration, disruption, payment claims — finding six or eight separate regimes with different windows is completely normal, and nobody on site is holding all of them in their head.

Two details do outsized damage. When the clock starts: "within X days of the event" is far worse than "within X days of becoming aware of the event" — delays often aren't visible as delays until later. What counts as notice: clauses requiring a specific form, addressee, or delivery method can invalidate a perfectly timely email that named the problem in plain English.

Where the law now pushes back

For decades the answer to "can they really enforce a 48-hour time bar?" was simply yes. Two Australian jurisdictions have built a safety valve:

Western Australia went first: under s 16 of its Security of Payment Act 2021, an adjudicator, court, or arbitrator can declare a notice-based time bar unfair — and of no effect for that entitlement — where compliance wasn't reasonably possible or would be unreasonably onerous, weighing things like bargaining power and when you could realistically have known about the event. See the WA guide.

Victoria copied the mechanism in its April 2026 reforms (s 13A), covering notices for payment, EOT, and release of security. Part of the same overhaul that abolished reference dates and excluded amounts — the VIC guide covers how much changed.

Everywhere else — including NSW and QLD — there's no blanket rule against time bars. Clauses that obstruct statutory payment rights can fall to anti-contracting-out provisions like NSW's s 34 (the courts have voided notice-deeming games on that basis), but a clearly drafted EOT time bar generally stands. And even in WA and VIC, the unfairness mechanism is a shield for genuinely impossible windows, with the onus on you. It is not a strategy.

Negotiate the regime before signing

Four asks, all standard:

1. Realistic windows — 10 to 20 business days for initial notices. If they opened with 48 hours, they expected to concede this.
2. Awareness-based triggers — windows run from when you became aware (or reasonably should have), not from when the event occurred.
3. Notice-first, particulars-later — a short holding notice preserves the claim, with particulars to follow in a reasonable period. This single change converts most time-bar risk into ordinary paperwork.
4. No bars on statutory rights — anything purporting to time-bar security-of-payment or prompt-payment claims is void in most of our markets anyway; strike it so nobody plays the game.

Read the time bars next to the LD clause: a heavy daily rate beside a 5-day EOT bar is one mechanism split across two pages — the rate does the damage, the bar deletes your defence.

Run the discipline after signing

Whatever survives negotiation becomes site routine, not office admin:

Extract every notice obligation into one list the day the contract is signed — clause number, trigger, window, form, addressee. This is the single highest-value hour in contract administration.

Keep a one-page holding-notice template. "We notify you under clause [X] that [event] occurred on [date] and may entitle us to an extension of time and/or costs. Full particulars will follow." Five minutes, claim preserved.

Default to noticing everything. A notice you later withdraw costs nothing and offends nobody who matters. A claim you didn't notice is gone. When in doubt, send it.

Log awareness dates. If a window runs from awareness, your site diary is the evidence of when awareness began.

How it plays out: one claim, three tripwires

A worked failure, assembled from the pattern lawyers see weekly. A structural steel sub hits a two-week delay when the slab hand-over slips — plainly the builder's problem. The subcontract requires: notice within 5 business days of the delaying event; full particulars with a program analysis within 10 business days of the notice; and updated particulars every 28 days. The foreman flags the delay in a site meeting (minuted, but not "written notice to the Contract Administrator per clause 41.2"), the office sends a proper notice on day 9, and particulars follow five weeks later once the program is rebuilt. Three tripwires, three strikes: the meeting minute probably isn't compliant notice, the formal notice is late, and the particulars are later. A $40,000 EOT-and-costs claim — with genuine merit — now depends entirely on the other side's goodwill, which is not a payment mechanism. The same events with a holding-notice template and a deadline list produce a compliant claim in ten minutes of admin. That's the entire difference.

The one-minute version

ContractorCounter Review extracts every notice obligation and time bar in the document — including the layered ones buried in the variations and latent-conditions clauses — and flags the windows short enough to hurt, each with a severity grade and a suggested ask. The deadline list writes itself before you've signed. US$19 per contract, and the subcontract checklist shows where time bars sit among the other clauses that decide your cash.

This article is general information, not legal advice. Whether a specific time bar is enforceable — or challengeable under WA's s 16 or VIC's s 13A — depends on the wording, the facts, and the forum. For claims worth real money, get advice early; time bars punish delay in seeking it.