Project delivery

What is precon in construction?

Precon, short for preconstruction, is the planning phase before construction starts, when the contractor and design team work out the budget, schedule, constructability, logistics, and buyout so the field can build without surprises.

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.

Precon is everything a builder does between "we might build this" and the first shovel. On a negotiated job, it can start while the architect is still drawing. On a hard bid job, it may be squeezed into the weeks between award and the notice to proceed. The goal is the same either way: find the problems on paper, where they are cheap, instead of in the field, where they are not.

Some contractors sell precon as a separate paid service, especially under construction management at risk and design-build. Others do it as part of chasing the work. Either way, it is real labor from estimators, PMs, and superintendents.

What happens in precon

  • Budgeting: conceptual estimates at each design stage, then a detailed estimate and a contingency.
  • Constructability: a constructability review by people who have built the thing before, flagging details that will not work.
  • Value engineering: value engineering options that keep function and cut cost.
  • Scheduling: a preliminary schedule, phasing, and identification of long lead items.
  • Logistics: crane locations, laydown, deliveries, and access.
  • Buyout planning: bid packages, subcontractor outreach, and bid leveling.

A worked example

Say a GC is hired for precon on a three-story, $14 million medical office building. At schematic design, the estimate comes in $1.1 million over the owner's budget. The precon team proposes changing the facade from full-height glazing to a mix of glazing and metal panel, moving a mechanical room to cut duct runs, and buying switchgear early. Those changes bring the number back in line.

During the same phase, the superintendent notices that the site has only one entrance off a busy road. The team plans a one-way delivery loop and staggered trade starts. None of this shows up in the contract sum, but it shows up in the margin at the end of the job.

Common mistakes

  1. Doing precon for free with no agreement on who owns the work product or whether the contractor gets the job.
  2. Leaving the field out. A precon plan written only by estimators often misses how the work actually goes in.
  3. Not handing it off. The best precon is wasted if the PM and superintendent never see the assumptions. A formal estimate to project handoff fixes that.
  4. Locking a number too early, before the design is developed enough to price.
  5. Ignoring procurement. Long lead items identified in precon still have to be ordered on time.

Precon also protects the relationship with the owner. When the budget, schedule, and big risks are agreed in writing before construction, there is less room for the argument that starts with "we never knew that was excluded." The precon deliverables become the shared reference both sides return to during the job.

Related terms

Precon leads into buyout, procurement, and the pre-construction meeting. Smart Business Automator carries the estimate, scope notes, and budgets from precon straight into the live project, so nothing gets retyped. See estimate to project handoff automation.

Frequently asked questions

What does precon stand for?

Preconstruction. It means the planning phase before construction starts.

Is precon a paid service?

Sometimes. Under CM at risk and design-build, owners often pay a preconstruction fee. On hard bid work, contractors usually absorb the cost of their own planning.

Who works in precon?

Estimators, preconstruction managers, project managers, and superintendents, along with the design team and often key trade partners like mechanical and electrical subs.

How long does precon take?

It depends on the project and delivery method. It can run from a few weeks on a hard bid job to many months on a negotiated project that starts during design.

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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