The Hospital St. Boise’s Luke’s has been operating almost as long as Idaho has been a state. In 1902, St. Luke’s began as a six-bed frontier hospital in a rural home in downtown Boise. Since then, the hospital has grown into a not-for-profit regional health system and community institution that draws patients from across the state, as well as northern Nevada and eastern Oregon.
With its iconic red brick buildings and seven-story central tower, the campus is an instantly recognizable landmark in the capital. Today, construction cranes, bulldozers and dump trucks have joined the familiar buildings as the health care provider prepares to serve the growing community for decades to come.
The state’s largest private employer, St. Luke’s is currently in the midst of one of the largest construction projects in the region, the $1.2 billion, 860,000-square-foot expansion of its Boise facility, known as the Downtown Commons Improvement Plan. The project includes a nine-story patient tower that will add 80 patient beds, bringing the facility’s total count to 500. There will also be room to add up to 133 beds in the future.
Led by Sandy, Utah-based Layton Construction, the project’s construction manager at risk, the expansion also includes seven new operating rooms for a total of 28 and a connected medical office building with 170,180 square feet of space for healthcare providers.
Locally fabricated steel supports the nine-story patient tower. Construction crews have worked to minimize noise and disruption next to the still-operating hospital.
Photo courtesy of Layton Construction
Construction began in 2024, with some smaller preparatory projects taking place in 2023. Construction of the hospital tower and medical office plaza is expected to last until 2029, with a projected opening of patient care in 2030. The current expansion project was preceded by the construction in 2019 of the children’s pavilion for pediatric services and the new floor of the parking lot in the city center, the garage and the pediatric service, and the new floor of the garage 2021. place.
The health system of St. Luke’s operates six hospitals and nearly 200 clinics throughout the region, but most high-level services such as cancer care, pediatric specialties and cardiac surgery are concentrated on the Boise campus, says Dennis Mesaros, vice president of population health at St. Luke for Boise, Elmore and McCall.
Although the downtown campus is the largest project in St. Luke in progress, is just one of several recent projects undertaken by the health system. In the year 2025, St. Luke’s opened a 330,000 square meter consolidated service center in nearby Meridian that centralizes its supply chains, distribution and pharmacy services. The hospital St. Luke’s in the resort community of McCall, north of Boise, received a 70,534-square-foot expansion and renovation in 2023, and a new clinic opened in the growing city of Nampa, west of Boise, in 2024.
In the year 2025, St. Luke’s reported operating income of about $4.5 billion, with the Boise flagship hospital having the highest revenue per patient at just over $1 billion. Mesaros says the expansion is being financed with existing resources and bonds issued by the health system.
“Reinvesting in our communities is an important part of the work we do,” says Sandee Gehrke, executive vice president and chief operating officer of St. Luke. “St. Luke’s is committed to providing all patients with the highest quality health care, regardless of their ability to pay.” Last year, the health system provided “$1.8 billion in community benefits, including $272 million in capital improvements, $176 million in community services and programs and $36 million in charity care,” Gehrke adds.
The expansion of the Boise campus was in the planning and approval process as the area experienced an increase in population beginning in 2010, placing it among the fastest growing metropolitan areas in the country. Idaho’s population is expected to double by 2040, says a spokeswoman for St. Luke, Christine Myron.
“When you look at the growth we’ve had, we just don’t have the inpatient capacity that our population needs,” Mesaros says. “We are the seventh community with the fewest beds in the country [and] I don’t want people to have to leave our communities to get care.”
Surrounded by city streets and existing buildings, the construction team is paying more attention to coordinating material deliveries.
Photo courtesy of Layton Construction
Planning and Preparation
The design firm Architectural Nexus of St. Luke’s of Salt Lake City and Boise-based Hummel Architects for the planning, programming and design of the expansion project, which was approved by the city in 2015.
Kelly Schreihofer, principal healthcare planner at Architectural Nexus, says the design firm has a 20-year history of working with St. Luke’s and has designed projects in Magic Valley, Nampa and Meridian.
“For the Downtown Commons Improvement Plan, our work began in 2009 with comprehensive master planning efforts for the Boise campus,” says Schreihofer. “Since then, the project has progressed through a series of carefully phased implementations, each contributing to the long-term overhaul of the campus. The goal has been to modernize and integrate facilities while maintaining continuous operations in a dense urban environment.”
St. Luke’s turned to the building team not only for the design and construction of the additions, but also to help prepare for how the hospital would function in the future.
“One of the main challenges was to align the service lines between floors and buildings,” says Schreihofer. “On the existing campus, clinical groups were often dispersed, sometimes across multiple buildings. By reorganizing and co-locating services, the new design improves the patient experience and supports a more integrated and modern model of care.”
“There were a lot of ‘preparation’ projects just to facilitate this phase we’re in now,” adds Jeremy Hobbs, vice president of Layton Construction, including demolition projects, moving some hospital operations to make way for connections and placing “a connector bridge over an existing building before the massive excavation began.”
The east tower will house 80 patient beds and maintain the familiar red brick look of the long-established community hospital.
Rendering by Architectural Nexus
Narrow spaces
Surrounded by city streets and existing hospital facilities, there was no room for construction trailers. Layton’s team built space on levels 4 and 5 of the adjacent parking deck to serve as offices, says Layton’s construction manager Patrick Kelly.
“Architectural Nexus is on our side and there is room for all business partners [as well as] The planning and design team at St. Luke,” says Kelly.
Teams meet daily to ensure constant coordination, and “having us all on site together helps with collaboration,” he says.
Hobbs says a significant effort is made to minimize disruption to regular hospital operations to avoid disrupting patient care and the healing process.
“We have to prioritize patient health. You always have to be aware that you’re building right next to a working hospital, and that means being aware of the noise, the vibrations, the smells, everything. [The construction work] it’s an orchestrated event, and we work with the Sant Lluc team to make sure we do the best we can.”
Hobbs says the construction team regularly makes changes to the work schedule and coordinates the delivery of materials to minimize the impact on hospital operations. Before construction began, additional glass panels were added to patient rooms to dampen construction sounds, and work can be stopped if things like vibrations are found to disrupt surgeries or equipment at the hospital, Myron adds.
Schreihofer says one of the “preparation” projects before construction was the relocation of MRI services. “Their MRI suite was right up against our building, so we built a new MRI facility on the other side of campus so there would be no disruption to services. At one point, we had to demolish a staircase that was next to cardiovascular surgery. There were months of planning for changes. [the hospital] schedule a couple of days a week, and then we worked 10- or 12-hour shifts Saturday through Tuesday, so we weren’t working during surgery hours.”
The hospital has committed to the Health and Human Services Sector Climate Commitment, a voluntary commitment to reduce emissions and build resilience in healthcare organizations. New energy-efficient mechanical systems will help reduce emissions, and steel was fabricated for the project in the Treasure Valley to reduce shipping distance.
