Project Management

Acceleration

Also known as: Schedule Acceleration, Crashing

Compressing a construction schedule by adding labor, shifts, or overtime to recover delay or finish earlier than planned.

Acceleration means shortening the planned duration of a project (or a portion of it) by adding resources, working overtime, running second shifts, or stacking trades. It happens for two reasons: to recover delay caused by weather, design changes, or owner decisions, or to finish ahead of contract for a bonus or a tenant's rent commencement deadline.

Acceleration costs money. Overtime hours run 1.5x straight time. Stacked trades reduce per-worker productivity by 10 to 30%. Second shifts add supervision overhead. When acceleration is owner-directed (or owner-caused), the contractor should document the directive in writing and price the cost as a constructive change order. Self-imposed acceleration to make up for the contractor's own delay typically cannot be passed through.

Frequently asked questions

What is the difference between acceleration and crashing?+

They are the same concept in practice. "Crashing" is the term used in CPM scheduling theory; "acceleration" is the term used in contracts and claims. Both mean shortening duration by adding resources at additional cost.

When can a contractor recover acceleration costs?+

When the owner directs acceleration in writing, or when the owner causes a delay that the contractor must work through to maintain the contract date. Document the directive, price the impact, and submit as a change order before performing the work.

How much does acceleration cost?+

Typically 10 to 40% on top of normal labor cost depending on how aggressive. Overtime adds the premium hours. Stacked trades reduce productivity. The math rarely beats avoiding the delay in the first place, but on a fixed end date it can be the only option.

Related terms

Critical Path

The sequence of dependent tasks determining a project's minimum duration. Critical-path delays push the entire schedule.

Change Order

A written modification to a construction contract documenting added, deleted, or altered scope plus price and schedule impact.

Baseline Schedule

The original approved project schedule used as the benchmark for measuring delay, acceleration, and progress.

Concurrent Delay

Two or more delay events affecting the schedule at the same time, with at least one caused by each party. A common claims defense.