The former Muirdale Tuberculosis Sanatorium, once a place for fresh-air cures, now sits at the heart of the Milwaukee County Research Park in Wauwatosa and is gearing up for its next act. City planners and developers are sketching out more apartments, plazas, and trails, and a newly announced four-story, 204-unit apartment building is expected to break ground this summer. The campus already mixes labs, offices, hotels, and open space, all orbiting around the sanatorium's preserved brick administration building.
According to the City of Wauwatosa, the city and developer Irgens entered a joint master-planning agreement in March 2025 to study infrastructure, zoning, traffic flow, and ways to weave in more mixed uses and public amenities. The city outlines goals that include better pedestrian and bicycle connections, new plazas, and shared green space to more tightly link the research park with surrounding neighborhoods. Earlier reporting on the partnership and public outreach came in a long-term urban makeover overview.
As reported by OnMilwaukee, the research park now includes office buildings, a medical office complex, two retail buildings totaling roughly 18,000 square feet, two hotels with 317 guest rooms, a 103-unit residential complex, and walking trails across the former sanatorium grounds. One of those hotels is being converted into apartments, and a separate four-story, 204-unit apartment building facing Mayfair Road has been announced, with construction slated to begin this summer. OnMilwaukee notes the park can host roughly 6,000 workers when the campus is busy.
From Sanatorium To Research Park
The main Muirdale administration building opened to patients on Nov. 22, 1915, and was designed in a U-shaped, vertical plan that combined medical services and patient rooms under one roof, according to the National Register file maintained by the Wisconsin Historical Society. Early records show the main building could accommodate about 205 patients, and the larger complex included cottages, a power plant, and landscape features aimed at providing the fresh-air therapy that was then standard treatment for tuberculosis.
“The research park lends itself beautifully with the walking trails and the beautiful features,” Mark Johnson, executive director of the Milwaukee Regional Innovation Center’s Technology Innovation Center, told OnMilwaukee, adding that the growing mix of uses helps attract workers and keep them on site.
The Technology Innovation Center, an incubator that operates out of the old Muirdale administration building, was founded in 1993 and bills itself as the region’s longest-running mixed-use business incubator, according to its website. A 2015 needs assessment by SB Friedman found that the incubator fills a distinct niche in the regional entrepreneurial ecosystem and recommended steps to support its continued viability.
What comes next is where things get interesting. The master plan framework is headed into public review, with the Wauwatosa Plan Commission and Common Council expected to weigh in on recommendations and projects as the study advances, Daily Reporter reported. Public outreach, including an open house and an online survey, is built into the process as the city and Irgens work out how additional housing, retail, and shared spaces could fit around the historic core of the former sanatorium.
