What is lead time (in construction)?

By Anthony McEvoy, owner’s representative

Last reviewed: October 2026

Lead time is how long you have to wait for equipment or materials after placing an order. Before using a supplier’s quoted lead time in the schedule, check when that wait begins and whether it includes delivery to the job site.

A supplier’s quoted lead time may start when an order is released or drawings are approved. Check whether it ends at shipment or arrival on site. For custom equipment, allow time for preparing and reviewing shop drawings, fabrication, and shipping.

What are long-lead items in construction?

Long-lead items are equipment or materials that take enough time to obtain that they can affect the project schedule. Common examples include electrical switchgear, generators, transformers, large mechanical equipment, elevators, and specialty fabricated items. The list changes with the project and the market, so confirm it with suppliers early.

What does this look like on a real project?

Long lead times on specialty and custom-built items come up on my projects all the time. A few catch the team by surprise, and most don’t. On my projects they have included valves, custom buildings, heaters, and programmable logic controllers.

On one process piping upgrade, the supplier quoted a lead time for a large specialty valve that would have pushed the work well past the window the owner had for it. We weighed the pros and cons of delaying the start of the project against putting in a short-term fix. The pipeline could temporarily do without the valve, so we fabricated and installed a spool piece, a short section of pipe that holds the valve’s place and allows the pipeline to be in service. The rest of the work went ahead on schedule, and the valve went in later, once it arrived, during a planned shutdown.

During project scoping, as soon as I’m made aware of material that seems custom or that I’m not familiar with, I get lead times and make the owner aware of the impacts before an initial project schedule is even set. That gives the owner time to discuss alternative material or to delay the project.

Why should owners care?

Owners need to know when a decision has to be made for equipment to arrive when the work needs it. Waiting to make that decision can push delivery back and delay the work that depends on it.

The supplier’s quote may count only the time after an order is released or drawings are approved. The design decisions and reviews needed before that point take time too. The schedule needs to allow for those steps, including the owner’s approvals and any equipment the owner is buying directly.

During design, the owner and project team should work backward from when each item is needed.

  1. Identify the long-lead items during design and agree on when the related owner decisions are needed.
  2. Put the owner’s own review and approval time into the schedule, with a named person responsible for each one.

What should owners check?

  • The team keeps a long-lead item list that was started during design, with one person on the team watching each item.
  • The schedule shows the full path for each one, from design decision to submittal approval to order release to delivery.
  • Owner reviews and approvals are in the schedule with their own durations.
  • Owner-furnished equipment is tracked in the same detail as contractor items.

Common questions

When does lead time start?

Check the supplier’s quote for what starts the clock. One electrical contractor’s published lead-time table counts from release of material, after it receives approved, stamped shop drawings, and contract award comes well before that point. Design decisions and shop drawing review sit in front of the quoted lead time, so give each one its own line in the schedule.

What is owner-furnished equipment?

Owners often use owner-furnished, contractor-installed (OFCI) equipment as a strategy to compress the project schedule. By buying the equipment directly, the owner can order a long-lead item months before the installation contract is awarded. But buying early moves several risks onto the owner’s plate. The installation contracts must clearly state who takes responsibility for receiving the delivery, secure storage, installation coordination, commissioning, and the warranty.

Related terms

The bigger picture is in our article on pre-construction sequence planning, which shows how dependencies and hand-offs push a project behind when reviews and approvals never get their own time in the schedule. That piece also explains how working backward from the date something is needed sets the real start date.

Once long-lead equipment starts setting your dates, we can go through the list with you.