Extension of Time Claims: What Contractors Need to Document

Extension of time (EOT) claims are one of the most common — and most contested — areas of construction contract administration. A contractor who doesn't understand the EOT process, or who fails to maintain the documentation required to support a claim, will often absorb delay costs that they were contractually entitled to recover.

What an EOT does (and doesn't) do

An approved extension of time does two things:

Moves the contractual completion date forward, reducing or eliminating the contractor's exposure to liquidated damages
Provides a basis for a delay costs claim (prolongation costs) in some circumstances

An EOT does not automatically entitle the contractor to payment for delay costs. It removes the LD exposure. Prolongation costs are a separate claim, with a separate evidentiary threshold.

When to give notice

Most contracts require the contractor to give notice of a delay event within a specified timeframe — commonly 14 to 28 days from when the contractor became aware of the delay. Failing to give notice within this window can — depending on the contract — bar the claim entirely.

This is one of the most commonly missed obligations in construction. The project team is focused on keeping the work moving; the paperwork for a delay event gets deferred until it's too late.

The rule: when something happens that could delay the programme, give notice that day. The notice can be brief. It just needs to be in writing and within the timeframe.

What to document

A well-documented EOT claim includes:

The delay event itself: what happened, when it happened, and why it was outside the contractor's control. Common EOT events include late design information, variations, client-directed changes, and specified inclement weather.

The impact on the programme: which activities were delayed, by how many days, and why those activities were on the critical path. This is where most claims fall over — contractors assert that they were delayed, but don't demonstrate that the delay was to a critical path activity.

As-planned vs. as-built programme: a comparison between the planned programme at the time of the delay event and the actual progress, showing the impact of the delay.

Contemporaneous records: daily site reports, superintendent's instructions, weather records, correspondence. The closer in time these records are to the event, the more weight they carry.

Critical path — why it matters

A delay to a non-critical activity doesn't entitle the contractor to an EOT, even if the delay was the client's fault. The claim must demonstrate that the delay affected the critical path — the sequence of activities that determines the project completion date.

If you don't have a current, maintained programme that shows the critical path, you can't make this demonstration.

Concurrent delay

Concurrent delay — where both the contractor and the client have caused delays that are running at the same time — is one of the most contested areas of EOT law. The treatment of concurrent delay varies between contracts and jurisdictions. Taking legal advice early when concurrent delay is present is strongly recommended.

Programme management and EOT documentation support is available through our Project Oversight service. Contact us if you need help with a current claim.