Liquidated Damages UK: Construction Contract Guide
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Construction projects rarely finish exactly on time, and when delays happen, the question of who pays for what can become messy quickly. Liquidated damages clauses are the construction industry's answer to this problem: a pre-agreed figure built into the contract that fixes the compensation payable if certain breaches occur, most commonly late completion.
Done well, these clauses save everyone from arguing over losses months or years after the fact. Done badly, they get struck out by the courts and leave the innocent party chasing actual losses the hard way. This guide walks through how liquidated damages work under English law, what makes a clause stick, and the practical points worth thinking about before you sign.
Whether you're an employer under a JCT contract or a contractor reviewing bespoke terms, the principles below should help you spot the issues that matter.
What this document is
A liquidated damages clause is a contractual provision that fixes, in advance, the amount one party must pay the other if a specified breach occurs. In construction, the breach is almost always a failure to complete the works by the contractual completion date, and the figure is typically expressed as a daily or weekly rate.
The sum is agreed at the point of contract, not worked out after the event. That matters, because it means the innocent party doesn't need to prove its actual losses to recover. If the contractor finishes six weeks late and the LD rate is a fixed sum per week, that's what's owed, full stop.
This pre-agreed approach is common across JCT, NEC and FIDIC forms of contract used in the UK, though the mechanics differ slightly between them. The clause usually operates alongside provisions dealing with extensions of time, sectional completion, and the issuing of a non-completion certificate, so it rarely stands alone in any meaningful sense.
How to use this document
- Work out what a realistic delay would actually cost. Before you agree an LD figure, think honestly about the losses a late finish would cause. Lost rental income, additional finance costs, staff redeployment, storage, and loss of use all feed into this. The figure doesn't need to be mathematically perfect, but it should bear some sensible relationship to the kind of losses you'd genuinely expect.
- Draft the clause with precision. A vague LD clause is a gift to the party in breach. The provision should clearly state the rate, the point from which it applies, the completion date or milestone it attaches to, and how it interacts with extension of time mechanisms. Ambiguity here tends to favour the paying party, because courts will not stretch the wording to fill gaps.
- Align the LD clause with the extension of time provisions. If the contract's EOT machinery breaks down, for example where there's no mechanism to grant extensions for employer-caused delay, the completion date can become 'at large' and the LD clause may fall away entirely. This is the so-called prevention principle, and it catches out employers who don't keep the two sets of provisions in lock-step.
- Keep records of the decision-making. If the enforceability of the clause is ever challenged, contemporaneous notes showing how the figure was arrived at can be invaluable. A paper trail suggesting the rate was a considered commercial estimate, rather than plucked from the air, goes a long way in defending against a penalty argument.
- Administer the clause properly during the project. Enforceability aside, LDs only work if the contractual machinery is followed. That usually means issuing the correct non-completion notice, deducting the sums in the right way, and making sure any revised completion date is properly certified. Get the procedure wrong and you can lose the right to deduct, even where the underlying clause is watertight.
Common questions
Q Can a liquidated damages clause be challenged as a penalty?
Yes. Following the Supreme Court's decision in Cavendish v Makdessi (2015), the test is whether the clause imposes a detriment out of all proportion to any legitimate interest the innocent party has in enforcing the obligation. The older 'genuine pre-estimate of loss' language has softened, but a rate that is extravagant or unconscionable compared with the real commercial interest at stake can still be struck down.
Q What happens if the liquidated damages clause is unenforceable?
If a court finds the clause to be a penalty, it falls away and the innocent party is left to claim general damages for breach of contract. That means proving actual losses flowing from the delay, which is harder, slower and more expensive than relying on an agreed figure. In practice, it often means recovering less than the LD figure would have produced.
Q Do liquidated damages cap the contractor's liability for delay?
Usually yes. In most standard form contracts, the LD clause is treated as the exclusive remedy for delay, meaning the employer cannot claim general damages on top. However, the position depends on the exact wording. Some clauses are drafted as a cap rather than an exclusive remedy, and some bespoke contracts preserve parallel rights, so the drafting really does matter.
Q What is 'time at large' and why does it matter?
Time becomes 'at large' when the contractual completion date is no longer binding, typically because the employer has caused delay and the extension of time machinery cannot cure it. When that happens, the contractor's obligation reduces to completing within a reasonable time, and the LD clause generally cannot be enforced. This is a major risk for employers who ignore EOT entitlements.
Q Can liquidated damages be set at nil or zero?
This is a well-known trap. Case law has gone in different directions on whether a 'nil' rate means the employer has agreed no damages are payable for delay, or whether general damages remain available. The safer course, if no LDs are intended, is to delete the clause entirely and deal with delay under general damages, or to state expressly what the parties intend.
Q Do liquidated damages apply to subcontractors too?
They can, and often do. Subcontracts frequently contain LD provisions mirroring those in the main contract, so that a main contractor facing LDs from the employer can pass that exposure down the chain. The same enforceability rules apply, and subcontractors should scrutinise the rate carefully, particularly where it reflects main contract exposure rather than the subcontractor's own scope.
Sources
This guide is based on primary UK law and official guidance.
- Guidance · HMCTSCourts and Tribunals Judiciary (case law guidance)judiciary.uk
- Official SourceSupreme Court: Cavendish Square Holding v Makdessi (2015)supremecourt.uk
- Guidance · UK Govgov.uk: Construction contracts guidancegov.uk
Legal disclaimer
This article is for general information only. It is a tool to help you find your way — not legal advice, and not a substitute for speaking to a qualified adviser about your situation.