What is a time bar in a subcontract, and when does it kill the claim?
A time bar is a clause requiring you to give notice of a claim (an extension of time, a variation, a delay cost) within a fixed window, commonly 5 business days. The critical distinction is what happens when you miss it: a notice-style clause delays or complicates the claim, while an absolute bar extinguishes it entirely. Absolute bars are the single most expensive clause type in Australian subcontracts.
The two species of time bar
Read the consequence, not the deadline. "The Subcontractor must notify within 5 business days" is a notice requirement. "The Subcontractor shall have no entitlement unless notice is given within 5 business days" is an absolute bar: the entitlement itself dies with the deadline. The same five days, radically different risk.
Absolute bars do their damage quietly. On a busy job, notices slip: a delay gets discussed on site instead of in writing, a variation gets done on a handshake. Under an absolute bar, each of those ordinary moments is a claim worth real money, extinguished.
Where the market sits
Five business days is aggressive but common; anything under five is high risk on its own. The negotiating asks that matter: a workable window (10 business days is a reasonable target), notice as a requirement rather than a bar, and a carve-out where the builder was aware of the event anyway.
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Scan my subcontract freeCommon questions
Are absolute time bars enforceable in Australia?
Courts have generally been willing to hold parties to clear time-bar drafting in commercial contracts, which is exactly why the clause is dangerous. Don't sign expecting it to be softened later. Negotiate it before signing; that's when you have the leverage.
What's the fastest way to protect myself on site?
Make written notice a reflex, not a decision: a short email the day anything changes (delay, direction, latent condition, extra work) beats a perfect letter sent a week later. Under an absolute bar, the habit is worth more than the wording.
Time bars and notice windows, by state
Keep reading
General information for Australian subcontractors, not legal advice. Statutory deadlines and details vary by state and change over time; verify them before relying on them. Written by Mat Kennedy at The Construction Contracts Co.