Image courtesy of the city of Waltham.

A 3-story Waltham building that hosts a Boston Sports Club has sold to an investment firm for $32.1 million.

The Davis Cos. sold 840 Winter St., near the Reservoir Woods office park in the city’s West End, to real estate investment firm Tritower Financial Group, according to documents filed in the Middlesex South Registry of Deeds.

The 126,000-square-foot building, built in 1999, was last sold in 2006 for $24 million.