Understanding Liquidated Damages in Construction Contracts

By

Josh Krissansen

Last Updated Apr 2, 2026

By

Josh Krissansen

Liquidated damages are intended to provide certainty in construction contracts, yet the Sydney CBD and South East Light Rail project is one example of how they can instead create significant disputes.

The project was quickly overtaken by scope changes, approval delays, and unresolved extension-of-time claims that resulted in a negotiated settlement worth hundreds of millions of dollars.

The case highlights a broader reality in construction projects. When liquidated damages are poorly structured, or delay processes break down during delivery, the clause that is meant to create certainty can instead trigger disputes over time, entitlement, and responsibility.

In this article, we explain how to avoid these disputes by exploring when liquidated damages are enforceable, how rates should be set, and how delay risk must be managed during delivery before it escalates into formal claims.

What are Liquidated Damages in Construction?

Liquidated damages are a contractual mechanism that sets a fixed daily rate payable by the contractor if the project is not completed by the agreed practical completion date.

In practice, the clause operates as follows:

• A fixed daily or weekly rate is agreed in the construction contract
• The rate is triggered by failure to reach practical completion, not delay in isolation
• Charges stop accruing when practical completion is achieved, meaning the works are usable even if minor defects remain
• The clause removes the need for the principal to prove actual financial loss caused by the delay
• Delay exposure is defined upfront, allowing both principals and head contractors to understand the financial risk

How Liquidated Damages Are Treated Under Australian Law

In Australia, disputes are judged on four legal factors that determine whether or not liquidated damages can be enforced.

1. Enforceability Depends on a Genuine Pre-Estimate

Liquidated damages are enforceable only where the agreed rate represents a genuine pre-estimate of the principal’s likely loss at the time the contract is entered into. Courts will not enforce rates that are excessive, arbitrary, or designed to punish the contractor rather than compensate for delay.

The assessment looks at what the parties could reasonably anticipate when the contract is entered into, not on the actual loss at the time the delay occurs. A difference between actual loss and the agreed rate doesn’t, on its own, make the clause unenforceable.

During this assessment, courts look for a rational connection to the anticipated impact of a delay, such as:

• Holding costs
• Financing exposure
• Lost revenue 

Flat rates that don’t consider the severity of a delay are more vulnerable to challenge, because they weaken the argument that the rate reflects a genuine pre-estimate of loss.

2. Practical Completion is the Trigger Point

Liquidated damages apply only where the contractor fails to achieve practical completion by the date set out in the contract.

This is an important principle, as a project can still reach practical completion even if minor defects or omissions exist, provided the works are fit for their intended purpose under the contract. If the contractor reaches practical completion by the stipulated date, even if there are defects to be rectified, the principal would not be entitled to liquidated damages.

On the other hand, where required approvals or certificates have not been obtained, practical completion cannot be achieved, and liquidated damages continue to accrue.

3. Extension of Time Controls Exposure to Claims

Extension of time (EOT) claims are an important control point for contractors looking to limit exposure to liquidated damages, as approved extensions move the date for practical completion and suspend liquidated damages for the approved delay period.

Even if a delay is excusable under the contract, contractors can still end up exposed to liquidated damages if EOT notices are submitted late or not in the correct form. In many projects, these missed or rejected extension claims turn a manageable delay into a much larger dispute later on.

4. Prevention and Concurrency Limit Enforceability

The prevention principle limits a principal’s ability to rely on liquidated damages where the principal has caused a delay due to:

• Late approvals
• Scope changes
• Access restrictions
• Failures in design information 

If the contract doesn’t include a workable extension of time mechanism for principal-caused delays, the agreed completion date can become unenforceable, which increases the risk of disputes.

When delays caused by the contractor and the principal happen at the same time, the outcome usually comes down to how the contract deals with concurrent delay and how clearly the programme evidence shows what actually happened. If schedules are poorly maintained or the delay analysis is weak, liquidated damages are often reduced or rejected, even where the contractor appears to be at fault.

How Liquidated Damages Are Calculated in Construction Contracts

How a liquidated damages rate is calculated at contract formation often determines whether it will hold up if a delay dispute arises later. Courts look closely at how the figure was derived and whether it reflects a reasonable estimate of the principal’s likely loss.

The steps below outline a practical approach to setting a commercially realistic rate.. 

1. Identify Delay-Sensitive Cost Exposure

Start by identifying the costs that increase directly if the project finishes late, as these are the losses the liquidated damages rate is meant to reflect.

Typical inputs include:

• Lost revenue or rent from delayed occupation
• Extended finance and holding costs
• Client-side supervision and project management costs
• Consultant engagement where design or certification teams remain active
• Temporary accommodation or storage costs caused by the delayed handover
• Insurance premiums that extend due to programme overrun

Costs incurred regardless of delay should be excluded. Including fixed overheads and sunk costs weakens the connection between the rate and the actual impact of delay.

2. Convert Expected Loss into a Daily Rate

Once delay-sensitive costs are identified, estimate the likely financial impact of a representative delay period and convert that exposure into a daily or weekly figure. For example, if a 30-day delay would create $300,000 in additional costs, this would equate to a liquidated damages rate  of around $10,000 per day.

Some projects set liquidated damages rates as a percentage of the overall contract value, but percentage-based shortcuts are harder to justify if the clause is challenged. Rates grounded in realistic delay costs are more likely to hold up.

3. Confirm That the Rate Is Commercially Reasonable

When liquidated damages are disputed, courts focus on whether the figure was commercially justifiable at the time the contract was signed, not whether it later matches the actual cost of delay. A figure that appears disproportionate to the anticipated impact of delay may be challenged as a penalty, even if the project later suffers significant losses.

Before committing the rate to the contract, confirm that the figure can be traced back to realistic delay costs, such as:

• Lost revenue
• Extended finance charges
• Additional supervision costs

This ensures that it reflects a genuine estimate of likely loss rather than an excessive or punitive amount.

What are the Most Common Liquidated Damages Disputes in Construction?

When liquidated damages disputes arise, they usually involve a small number of recurring legal and contractual issues. Understanding these patterns helps project teams identify where delay exposure is most likely to escalate into formal disputes.

The most common disputes fall into five categories.

1. Penalty and Enforceability Challenges

   Contractors often argue that the liquidated damages rate is excessive and not a genuine pre-estimate of loss. The dispute centres on whether the rate was commercially justifiable at the time of contract formation.
   
   Where a rate is struck down as a penalty, principals lose the certainty that liquidated damages were meant to provide and must instead prove actual loss. 

2. Extension Of Time Administration Failures

   Many disputes stem from the Extension of Time (EOT) processes breaking down in practice. Common failure points include late notices, incomplete cause-and-effect analysis, and claims that are not assessed within contractual timeframes
   
   Rejected or unprocessed extensions can leave contractors exposed to liquidated damages they could otherwise have avoided.

3. Concurrent Delay Disputes

   Disputes often arise where two delays overlap: one caused by the principal and the other by the contractor. Contractors often argue that the principal is at fault for both, and that concurrent delay should entitle them to time relief.
   
   What happens next often comes down to how the contract deals with concurrent delay and how strong the programme evidence is. If schedules are poorly maintained or the delay analysis is done after the fact, it becomes much harder to demonstrate what actually caused the delay.

4. Practical Completion Disputes

   Liquidated damages stop accruing when practical completion is achieved under the contract, but principals and contractors don’t always agree on when practical completion is actually reached.
   
   Principals may withhold certification due to minor defects, incomplete documentation, or outstanding approvals, while contractors often argue that the works are fit for their intended purpose despite minor outstanding items.

5. Nil or Nominal Liquidated Damages Rates

   When actual loss is difficult to calculate, or if there's a need to preserve the ability to pursue higher claim amounts later, construction contracts will often include a nil or nominal rate as a placeholder.
   
   This lack of specificity can open up disagreements, particularly when the principal later seeks to recover losses far exceeding the nominal rate stated in the contract.
   
   Contractors often dispute these kinds of claims from principals, but courts have generally found that a nominal liquidated damages rate does not necessarily prevent a principal from pursuing general damages unless the contract clearly excludes that right.

How to Mitigate Liquidated Damages Risk in Construction

Managing liquidated damages risk requires consistent control at several stages of the project lifecycle, from contract drafting and delay administration through to programme monitoring and practical completion.

The five controls outlined below set out the actions project teams can take in each of these areas to limit liquidated damages exposure and reduce the likelihood of disputes.

1. Define Practical Completion and Delay Rules Clearly

Prevent disputes over definitions by making sure the contract clearly sets out:

• What constitutes practical completion
• How minor defects impact practical completion
• Which approvals or certificates must be obtained before completion can be certified
• Notice requirements and assessment timeframes for extension of time claims
• How delay entitlement is handled when responsibility is shared or overlapping delays occur

When these definitions are clear from the outset, delay can be assessed consistently during delivery, reducing disputes about whether liquidated damages should apply and when they stop accruing.

2. Control Liquidated Damages Exposure Through Extension-of-Time (EOT) Claims

If EOT claims are submitted late, rejected, or left unresolved, the completion date does not move, and liquidated damages exposure continues to build even where delay entitlement may exist.

To manage this risk effectively, contractors must:

• Issue delay notices within the timeframes required by the contract
• Document the cause of each delay event
• Update the programme to reflect the impact on the critical path
• Track unresolved or disputed extension claims

These steps help ensure the completion date is adjusted where delay entitlement exists, rather than leaving contractors exposed to liquidated damages.

3. Record Who Caused the Delay

Many liquidated damages disputes ultimately boil down to a single question:

Who caused the delay?

Where responsibility is unclear, contractors can remain exposed to liquidated damages even when the delay was triggered by design changes, late approvals, restricted access, or incomplete information from the principal.

To protect delay entitlement, project teams should document delay events as they occur, including what happened and when, who was responsible, and how it affected the programme or critical path.

When this link between the event and its programme impact is clearly documented, project teams can demonstrate why the completion date should move and support extension of time entitlement if the delay is later disputed.

4. Track Programme Slippage Early

Review programme updates regularly and track changes to the critical path, so emerging delays are identified early.

When float begins to shrink or milestones start drifting, investigate the cause of the delay immediately. If the schedule shows that completion may be threatened, assess whether work can be resequenced, resources increased, or an extension of time claim prepared.

Acting on these signals early can help prevent delays from accumulating unnoticed and reduce the risk that the project reaches the completion date with unresolved liquidated damages exposure.

5. Avoid Certification Delays at Practical Completion

Even when construction work is largely finished, missing approvals, unresolved defects, or incomplete documentation can delay certification and allow liquidated damages to continue accumulating.

To protect the completion milestone:

• Identify inspection and certification requirements early
• Address defects before the final stages of the programme
• Track critical approvals such as fire, accessibility, and services certification

Managing these requirements proactively helps ensure practical completion can be certified as soon as the works are ready for handover.

Making liquidated damages work in practice

Liquidated damages work best when the rate is realistic, practical completion is clearly defined in the contract, and extension of time processes are actively managed during delivery.

When those fundamentals are in place, liquidated damages operate as intended: as a commercial safeguard, not a source of claims, disputes, and unexpected financial risk.

Written by

Josh Krissansen

68 articles

Josh Krissansen is a freelance writer with two years of experience contributing to Procore's educational library. He specialises in transforming complex construction concepts into clear, actionable insights for professionals in the industry.

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