Field

What is mobilization in construction?

Mobilization is everything a contractor does to get set up on a job before real production begins: moving equipment, setting up trailers and utilities, getting permits and insurance in place, and bringing crews to the site.

Two construction professionals review paper plans beside a tablet at a jobsite workbench.
Plan reviews connect field conditions, drawings, and the next decisions on a job. AI-generated illustration.

Mobilization is the startup phase of a job and the cost that comes with it. Before the first footing gets dug, someone has to haul the excavator in, set the office trailer, run temporary power, put up fence and signs, get the dumpster delivered, and file the bonds and certificates the owner asked for. On many contracts mobilization is its own line item, usually a lump sum, and it is often one of the first things billed.

The reverse at the end of a job is demobilization: pulling equipment out, removing temporary facilities, and cleaning up the site. Some contracts lump the two together. Others price them separately.

What mobilization typically covers

  • Hauling heavy equipment, including lowboy trucking and any permits for oversized loads.
  • Office and storage trailers, sanitation, and temporary utilities.
  • Site fencing, erosion control setup, and signage.
  • Bonds, insurance certificates, and permits needed before work starts.
  • Crew travel to a remote site, and lodging if the contract allows it.
  • Initial layout and survey control.

Exactly what belongs in mobilization depends on the spec section that defines it. Read that section, because some owners put temporary facilities in general conditions instead.

How mobilization is paid on federal jobs

On Department of Defense construction, DFARS clause 252.236-7004, Payment for Mobilization and Demobilization, covers jobs with major mobilization expense. The government pays mobilization and demobilization of the contractor's plant and equipment at the lump sum bid for that item, split into a percentage paid when mobilization at the site is complete and the rest when demobilization is complete. DFARS 236.570 tells contracting officers to generally allocate 60 percent of the lump sum to mobilization and never more than 80 percent.

The clause also lets the contracting officer ask for cost data if the bid price for mobilization does not reasonably match the cost. If the contractor cannot justify it, the government pays actual mobilization and demobilization costs and holds the rest until final payment. In other words, padding the mobilization line to collect cash early can backfire. State DOTs and other public owners have their own rules, often in their standard specifications.

A worked example

Say a sitework sub has a $900,000 contract on a private warehouse pad. Its schedule of values carries mobilization at $36,000. Hard costs to get set up come to about $28,000: $9,500 in lowboy trips for a dozer, excavator, and roller, $6,000 for a trailer and sanitation, $4,500 for silt fence and a construction entrance, and $8,000 in bond and insurance premiums. The other $8,000 covers the first few days of crew time spent on layout and setup instead of production.

The sub bills the full $36,000 on its first pay application, less retainage. That early cash covers money already spent. The owner's reviewer accepts it because the line is reasonable and backed by delivery tickets and premium invoices.

Common mistakes and disputes

  1. Front-loading mobilization far above real cost. Owners and lenders notice, and it can lead to rejected pay apps. See front-loading.
  2. Leaving out remobilization. If the owner stops the job or phases it, every extra move costs money. Price it or reserve the right to a change order.
  3. Billing mobilization before you are actually on site with equipment.
  4. Forgetting that a notice to proceed often starts the contract clock, so slow mobilization eats schedule.

Related terms

Mobilization ties to the site logistics plan, equipment cost, and progress billing. Smart Business Automator tracks equipment and material shipments to each site and puts the mobilization line on the first invoice once the work qualifies. See construction accounts receivable automation.

Frequently asked questions

Is mobilization a direct cost or overhead?

It is a job cost. Mobilization is incurred for a specific project, so it belongs in that job's budget and cost codes, not in company overhead.

When can a contractor bill for mobilization?

Usually once the contractor is set up on site, according to the contract and the schedule of values. Some owners pay part at mobilization and the rest later in the job.

What is remobilization?

Remobilization is moving back onto a site after leaving it, often because of phasing, a suspension, or owner delays. It is usually extra work and should be priced through a change order.

How much of a contract is mobilization?

It varies by job size, location, and equipment. Some public owners cap the mobilization item. On DoD jobs using the DFARS clause, the lump sum is split between mobilization and demobilization, generally 60 percent to mobilization.

Sources

  1. Cornell LII: 48 CFR 252.236-7004, Payment for Mobilization and Demobilization
  2. Cornell LII: 48 CFR 236.570, Additional provisions and clauses
Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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