Acceleration Claims in Construction Projects: What Engineers Must Know

1. Introduction

Time is money in construction. Projects are priced, financed, and delivered against strict deadlines. When delays occur, owners often refuse to extend completion dates. Instead, they insist on recovery or even earlier completion. This puts contractors in a tough spot, as they must accelerate performance, often at significant cost.

Acceleration claims arise when contractors seek compensation for the additional costs of working faster than planned. These claims are common in EPC and infrastructure disputes, yet they remain among the most misunderstood.

At Aegis, we frequently see acceleration claims bundled with delay claims. This article explains what acceleration is, how claims are categorized, the elements contractors must prove, and what engineers and project managers should do to protect their entitlement.

2. Types of Acceleration

Directed Acceleration

Directed acceleration occurs when the owner issues a clear instruction to recover slippage or meet an earlier completion date. For example, an order to install 5,000 feet of piping in 20 days when the plan allowed 30 days.

Constructive Acceleration

Constructive acceleration happens when the contractor is entitled to a time extension, but the owner denies or ignores the request. To avoid liquidated damages, the contractor accelerates to meet the original completion date.

Voluntary Acceleration

Voluntary acceleration occurs when the contractor speeds up for its own reasons, perhaps to free resources for another job. These costs are usually not compensable.

Aegis Insight: Many disputes stem from confusion between directed and constructive acceleration. If the owner’s actions deny legitimate extensions, even silence or pressure can amount to an order to accelerate. Contractors must record these moments carefully.

3. Elements of an Acceleration Claim

Tribunals generally look for five elements when evaluating acceleration claims:

1. An excusable delay occurred.

2. The contractor requested an extension.

3. The extension was denied or ignored.

4. The owner insisted on original completion.

5. The contractor accelerated and incurred additional costs.

   
   

Without this chain, entitlement is weak. For engineers and project managers, the practical step is clear: always issue notices, always request extensions, and always document responses.

4. International Perspectives

United States

In the United States, constructive acceleration is a recognized doctrine. Contractors may recover costs where they accelerate after a denial of extensions.

Commonwealth

In Commonwealth countries, the approach is more cautious. Acceleration is typically treated as a variation or breach of contract rather than a standalone doctrine.

Middle East (Civil Law)

In the Middle East, acceleration is often assessed through good faith obligations. Owners who deny time and then demand completion may be held liable for associated costs.

5. Protocol Position

The Society of Construction Law Delay and Disruption Protocol (2017) is clear: constructive acceleration claims are problematic. It advises that parties should avoid unilateral acceleration and instead agree on the scope, programme impact, and reimbursement before acceleration begins.

AACE® International (Recommended Practice 29R-03) recognizes three types of acceleration: directed, constructive, and voluntary. To succeed with an acceleration claim, a contractor must prove excusable delay, a request for extension, denial of that extension, acceleration of the works, and measurable additional costs. AACE stresses that acceleration cannot be shown through baseline vs. final comparisons alone; it must be demonstrated using contemporaneous CPM updates and supported by payrolls, equipment logs, and invoices. Global or lump-sum claims are discouraged; costs must be causally linked to the acceleration measures themselves.

At Aegis, we echo this guidance. Contractors who accelerate without agreement often face difficulty recovering costs later. Owners who press contractors informally create risks of constructive acceleration claims that could have been avoided by issuing proper extensions.

6. Notice Requirements

Timely notice is the cornerstone of any acceleration claim.

• Contractors must notify excusable delays promptly.

• Requests for extensions should be clear and supported by records.

• If an extension is denied, contractors must state in writing that any pressure to meet original dates will be treated as acceleration.

  
  

Aegis Insight: In many disputes, contractors accelerated but never issued notices. Tribunals then dismissed claims not because costs weren’t real, but because entitlement had no contractual foundation.

7. Timing of Extensions

Extensions granted too late are worthless. If contractors have already accelerated, belated extensions do not cure the problem.

Similarly, partial extensions can still justify acceleration claims. If the contractor was entitled to 60 days but only 30 were granted, acceleration of the remaining 30 is compensable.

Owners must be aware that silence or delayed responses can amount to denial, triggering constructive acceleration exposure.

8. Contract Clauses and “No Damage for Delay”

Many contracts allow owners to instruct acceleration. Enforceability depends on whether the contract also provides for cost reimbursement. If acceleration is ordered without reimbursement, risk is unfairly shifted.

“No Damage for Delay” clauses are common but often challenged. Where owners deny extensions, interfere, or act in bad faith, tribunals may set such clauses aside.

9. Identifying Acceleration in Schedules

Acceleration is demonstrated through programme evidence. Tribunals look for clear signs that activities were performed faster due to added resources.

Table: How Acceleration Appears in Scheduling

Scenario	Planned	Actual	Finding
Normal progress	30 days planned	30 days actual	No acceleration
With acceleration	30 days planned	20 days actual (extra shifts, overtime)	Acceleration proven
Claimed acceleration but delayed	30 days planned	35 days actual	Delay, not acceleration

Analyses must use updated CPM schedules, resource histograms, and man-hour records. Static comparisons are rarely sufficient.

10. Documentation

Robust records are indispensable. Essential documentation includes:

• Daily payrolls (regular and overtime hours).

• Equipment logs (utilization, downtime).

• Progress reports (units installed vs. planned).

• Subcontractor invoices and premiums.

• Original budgets and revised estimates.

• Updated CPM schedules showing resequencing.

  
  

Without these, acceleration costs risk being dismissed as unproven.

11. Acceleration Damages

Recoverable acceleration costs may include:

• Overtime and premium wages.

• Additional shifts or crews.

• Equipment rentals, fuel, and maintenance.

• Expediting deliveries of materials.

• Extra supervision and site overhead.

• Subcontractor acceleration premiums.

• Loss of productivity due to stacking or resequencing.

• Sometimes allocations of home office overhead.

  
  

The Measured Mile

Loss of productivity is often proven using a measured mile, comparing productivity in unimpacted work against accelerated periods. However, this method only works if a truly unaffected baseline exists. In many projects, early periods are already disrupted, weakening the analysis.

12. Practical Guidance

For Contractors

• Always request extensions before accelerating.

• Confirm in writing when owner actions are treated as acceleration.

• Maintain monthly programme updates.

• Document costs with payrolls, invoices, and logs.

• Avoid voluntary acceleration unless contractually agreed.

  
  

For Employers

• Grant extensions promptly where justified.

• Avoid vague instructions that imply acceleration.

• Draft clear acceleration provisions, including reimbursement.

• Monitor contractor notices and act transparently.

  
  

13. Tailpiece

Acceleration claims are costly, complex, and evidence-heavy. They usually arise alongside delay claims, but they add unique risks for both contractors and owners.

The doctrines are straightforward: without excusable delay, notice, denial, and incurred costs, entitlement does not exist. Yet even where those elements are met, tribunals scrutinize records, programmes, and substantiation.

For engineers and project managers, the lesson is practical: acceleration claims are not decided by contract language alone; they are decided in schedules, notices, and site records.

At Aegis PMC, we help contractors and subcontractors recognize when acceleration is directed or constructive, document impacts properly, and present defensible claims that withstand tribunal scrutiny.

👉 Facing acceleration pressures? Contact Aegis today to protect your entitlement before costs spiral.