J.P. Cullen

J.P. Cullen is a fifth-generation family builder founded in Janesville, Wisconsin, in 1892, and it still runs the company from Janesville with offices in Madison and Milwaukee. The firm says it’s a $950-million-plus operation with more than 850 employees and registrations in 22 states. Its work spans manufacturing and biotech plants, healthcare, higher education and historic restoration, and it self-performs as much of each job as it can. That shows on Kikkoman Foods’ new soy sauce plant in Jefferson, Wisconsin, which opened Sept. 18, 2026. Cullen worked under EPC contractor CRB there as the subcontractor for concrete foundations and slabs, masonry and structural steel erection.

Project size is the first thing worth knowing, because it is unusual: jobs range from $1,000 to more than $100 million. A contractor of this scale that still takes a thousand-dollar call is making a deliberate choice about the kind of client relationships it wants, and it shows in how the service list is built.

Referendum services sit in that list next to preconstruction and design-build, aimed squarely at school districts that have to win a public vote before a building can be funded. Historic restoration is a named capability too, as are prefabrication, virtual design and construction and sustainability consulting. Self-performed work is listed as a service in its own right, with the company saying it trains its people so it can self-perform as much of a project as possible.

The firm operates as a union shop and describes that as a commitment it has kept throughout its history. An Industrial Services arm supplies skilled labor and field expertise directly to clients, which is a different product from building something for them, and the industrial side works nationwide while general building work concentrates on Wisconsin, northern Illinois and northeast Iowa.

Five markets carry the work: commercial, education, healthcare, industrial, and science and technology.

Two numbers say more about the company than the revenue figure does. Ninety-eight team members have been there twenty years or more, in a trade where that is rare. And ownership passed to the fifth generation of the family in 2022, which is the structural reason the long tenures are possible. The firm took the AGC Alliant Build America Grand Award in 2015, and runs offices in Janesville, Madison and Milwaukee.