Graycor Construction Company

Graycor Construction Company is the building arm of Graycor Inc., headquartered in Oakbrook Terrace, Illinois. The company traces its start to 1921, when Edward Gray set up a Chicago concrete-breaking business, and it still leans on heavy industry: steel, power and manufacturing clients sit alongside logistics, healthcare, retail and corporate work. Services listed on its site include general contracting, design-build, self-perform and preconstruction, run from offices in Illinois, Indiana, Arizona, North Carolina and California. The site doesn’t publish a headcount. Graycor Construction Company leads the design-build team, with Helmkamp Construction Co., on the Wieland East Alton Hot Rolling Mill Modernization, a $500 million job that started in June 2024 and topped out in January 2026.

Seven offices define where Graycor can realistically staff a job: Oakbrook Terrace and Chicago in Illinois, Phoenix, Portage in northwest Indiana, Charlotte and Raleigh in North Carolina, and San Jose. Portage and Phoenix are the telling ones — a yard in the Calumet industrial corridor and a presence in the Southwest construction market are not where a firm goes for commercial fit-out work. They are where heavy manufacturing and advanced facilities get built.

The market list reflects that: manufacturing, advanced facilities, logistics and distribution, power and gas, plus retail and shopping, corporate, cultural and educational, living and lodging, healthcare, and entertainment and dining. Ten categories from one contractor is broad, and the industrial half is clearly the anchor.

Two service lines are worth separating out from the standard general-contracting menu. Integrated project delivery is a contract structure, not a buzzword — it puts owner, designer and contractor into a shared-risk agreement, and a contractor that lists it has done the legal and accounting work to operate that way. Live environment is the other: construction inside a facility that keeps running, which on a plant or a hospital means phasing, shutdown windows and temporary systems rather than a clear site. Alongside those, the firm lists general contracting, design-build, self-perform work, preconstruction, MEP coordination and construction technology.

On credentials, the company publishes its contractor license numbers directly — ROC209363, 53040, 865964, GCQA002582 and GCCO002569, and G106614 — which is faster to verify than requesting them. Recognition in 2025 came from two directions: Associated Builders and Contractors named Graycor Inc. a top-performing construction company in February, and Owens Corning named it a top supplier in September. A manufacturer naming a contractor is a different signal from an association award; it reflects installed volume and field performance on that manufacturer’s systems.

Where the site is quiet: no headcount, no stated ownership structure, no safety award record and no association memberships published, despite describing a century of experience. For an owner evaluating Graycor on a self-perform industrial package, the items to request are the EMR and safety statistics, the self-perform trades available in your region, and references from the office that would actually run the work.