Construction Firm Takes Full Building in St. Louis

ARCO National Construction, a design-build general contracting firm, has added 35,000 square feet of office space at Clayton Executive Center I in St. Louis, where it now leases the entire four-story building. ARCO had been leasing 60,000 square feet of space since January 2023.

The expansion brings the 95,000-square-foot office building at 7930 Clayton Road in the Clayton submarket to full occupancy. The property’s last big tenant, healthcare administration company Centene, vacated its 80,000-square-foot space in 2022.

An affiliate of Stanton Road Capital has owned the asset and Clayton Executive Center II, a 63,034-square-foot office building at 7980 Clayton Road, since February 2018. The private investment management firm, which owns and operates more than 6 million square feet of commercial real estate assets throughout the U.S., purchased both properties from Veritiv in a $26.2 million portfolio deal, according to Yardi Matrix data.

Clayton Executive Center I was built in 1982, while and the second asset was completed a year later. Clayton Executive Center II is fully leased by SSM Health, a Catholic nonprofit health  system operating in the Midwest.

Sansone Group, which is the property and leasing manager for the assets, handled the transaction. Tom Bajardi, Sansone Group executive director, represented ownership in the transaction.

Long-standing relationship

ARCO’s expansion at the Clayton building, which serves as its headquarters, comes as the company is growing. The firm has a strong nationwide project pipeline and is seeing increasing demand from various product types and markets.

ARCO and SRC have a long-standing relationship with ARCO, constructing several tenant build-outs and property improvement projects across SRC’s national portfolio. ARCO recently completed construction of several new amenities at the Deloitte Building, a 12-story, 260,000-square-foot office building in downtown St. Louis, for SRC.

Those amenities include a fitness center, a 100+ person conference facility, a Wi-Fi-enabled tenant lounge and grab-and-go food and beverage options. The amenity enhancements helped draw a new tenant to the property in April 2025, when Baker Sterchi Cowden & Rice LLC, signed a lease for the entire ninth floor, totaling 22,800 square feet.

Submarket seeing strong tenant demand

SRC and Sansone Group officials say ARCO’s decision to occupy the full building reflects the strength of the location and quality of the asset. It has a strategic location within the Clayton submarket, considered St. Louis’ premiere office market, and is visible from Interstate 170. Located just outside the city limits, Clayton is the St. Louis County seat and home to several corporate headquarters.

Cushman & Wakefield’s first-quarter Marketbeat report for St. Louis and its suburban submarkets noted that Clayton continued to benefit from strong tenant demand. The submarket saw 88,245 square feet of new leasing activity in the first quarter of 2026.

The report stated Clayton is the only submarket in St. Louis to record positive annual absorption totals over each of the last three years. The overall vacancy in the Clayton submarket for the first quarter was 15.2 percent, an 80-basis-point decrease year-over-year.

In its first-quarter report, Colliers noted the overall St. Louis office market continued to show incremental stabilization. Overall vacancy held steady at 24.7 percent, with submarket shifts driven by a limited number of large move‑ins and move‑outs.

In Clayton, the ARCO lease expansion bucked the local trend, which saw leasing demand mostly coming from transactions for spaces under 15,000 square feet. Colliers reported the smaller-space leases are reflecting tenants’ preference for flexibility.