Design Mechanical is going all in on Thornton, signing a 10-year lease for the entire Building 1 at Creekside Innovation Park and locking in 129,140 square feet as the development's anchor tenant. Construction is set to kick off in June, with the project slated to deliver in the second quarter of 2027. The move plants one of the region's sizable mechanical contractors squarely in the fast-growing North I-25 industrial corridor and gives Creekside some instant credibility before the first scoop of dirt is turned. Developer OCC Industrial has been marketing the site as speculative space geared toward light manufacturing, R&D, and distribution users.
As reported by ColoradoBiz, the deal covers the full 129,140-square-foot Building 1 and was inked before construction even began. James Carolan, chief investment officer at OCC Industrial, framed the timing as a major vote of confidence, saying, "Securing Design Mechanical as our anchor tenant before a single shovel hits the ground is exactly the kind of validation that defines a well-positioned project."
Building Specs And What Is Still Up For Grabs
The Creekside campus totals roughly 252,200 square feet across two buildings at the southwest corner of East 148th Avenue and Washington Street. Listings from Cushman & Wakefield show Building 1 as fully spoken for, while Building 2 clocks in at about 123,060 square feet and is still available. The broker materials flag the project as a 2027 delivery and list Tyler Smith, Alec Rhodes, and Aaron Valdez as the leasing contacts.
Why Thornton Made The Cut
Design Mechanical, backed by Comfort Systems USA, zeroed in on Thornton largely for its access to I-25 and the surrounding labor pool. Those two factors pushed the city to the top of the company's shortlist. "Thornton is where we want to be for the long term, and Creekside gave us the confidence to commit," Bob Frese, president of Design Mechanical, told ColoradoBiz.
Comfort Systems USA reported roughly $9.1 billion in revenue and carried an approximately $12 billion backlog in 2025, according to its 2025 Form 10-K, detailed in Comfort Systems USA. Those numbers give some context for the scale of work that could eventually flow through the new Thornton facility.
What Happens Next
The City of Thornton signed off on rezoning and a conceptual site plan in January, clearing the path for OCC Industrial to proceed, according to the City of Thornton. With approvals in hand, OCC is ramping up construction this month while marketing Building 2 for lease or sale. Prospective users can find leasing details through Cushman & Wakefield and the project's site.
