The True Cost of Construction Delays: Liquidated Damages, EOT & Prolongation
Published July 21, 2026 · By buildercalc Commercial Engineering Team · Cited Standard: SCL Protocol 2nd Ed / AIA A201 / FIDIC 8.4
Construction project delays carry compounding financial risks that ripple across project owners, general contractors, and subcontractors. Under standardized commercial contract frameworks—including AIA A201-2017 and FIDIC Red Book Clause 8—delays are categorized into three distinct legal classes: non-excusable delays, excusable non-compensable delays, and compensable delays. Non-excusable contractor delays trigger daily liquidated damages (LDs) to compensate the owner for lost revenue or financing debt. Excusable delays caused by force majeure or neutral events grant Extension of Time (EOT) relief from LD penalties but provide zero monetary reimbursement. Compensable delays caused by owner actions or scope changes entitle contractors to both EOT completion date relief and monetary compensation for time-related Preliminaries & General (P&G) site overhead prolongation costs. Accurately analyzing delay events on the critical path is vital for protecting cashflow and resolving commercial claims.
Commercial Delay Classification Framework
In commercial construction administration, evaluating a delay claim begins by establishing whether the delay impacts the project's critical path and determining contractual liability. Standardized guidelines set by the Society of Construction Law (SCL) Delay and Disruption Protocol (2nd Edition, 2017) and AIA Contract Documents A201-2017 § 8.3 dictate three distinct delay classifications:
- 1. Non-Excusable Delays: Delays caused solely by contractor fault, slow progress, or subcontractor delays. The contractor receives no time extension and must pay daily Liquidated Damages (LDs) for every calendar day beyond the contract completion date.
- 2. Excusable Non-Compensable Delays: Delays resulting from neutral events beyond either party's control, such as abnormal force majeure weather, acts of God, or national labor strikes. The contractor is granted Extension of Time (EOT) relief from LDs but receives no money for prolonged site overhead.
- 3. Compensable Delays: Delays caused by project owner defaults, late drawings, site access restriction, or unissued change orders. The contractor is entitled to both an Extension of Time (EOT) and financial reimbursement for daily time-related Preliminaries & General (P&G) site costs.
Liquidated Delay Damages vs Site Prolongation Costs
Liquidated damages represent a pre-agreed estimate of daily financial losses incurred by the owner when a project exceeds its contract completion milestone. According to standard contract law principles (Restatement Second of Contracts § 356 and FIDIC Sub-Clause 8.7), liquidated damages must reflect reasonable pre-estimates of actual harm rather than punitive fines.
Conversely, when an owner delays a contractor on the critical path, the contractor incurs daily time-related overhead expenses—known as Preliminaries & General (P&G) prolongation costs. These costs include site management staff salaries, tower crane rentals, field office trailers, site security, and temporary utilities.
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Frequently Asked Questions (FAQ)
What is the difference between non-excusable, excusable non-compensable, and compensable delays?
Non-excusable delays are caused by contractor default and trigger liquidated damages. Excusable non-compensable delays (force majeure) grant time extension without money. Compensable delays are caused by owner default and grant both time relief and prolongation money.
How are daily Liquidated Damages (LD) assessed under AIA A201 and FIDIC?
Liquidated damages are pre-agreed daily rates stipulated in the contract to compensate the owner for lost revenue or financing costs, governed by AIA A201 § 8.3 and FIDIC Sub-Clause 8.7.
What is a compensable prolongation claim?
A prolongation claim compensates a contractor for time-related general conditions overhead (site staff, equipment rentals, utilities, site office) incurred during an owner-caused delay.
How does the Society of Construction Law (SCL) Protocol handle concurrent delay?
Under the SCL Delay and Disruption Protocol (Core Principle 10), when employer delay and contractor delay occur concurrently on the critical path, the contractor is entitled to an extension of time but no financial compensation for the overlapping period.
- Society of Construction Law (SCL) Delay and Disruption Protocol (2nd Edition, February 2017).
- American Institute of Architects (AIA) Contract Documents A201-2017 General Conditions of the Contract for Construction.
- FIDIC Conditions of Contract for Construction (Red Book, 2017 Edition), Clause 8 (Commencement, Delays and Suspension).