Nantucket Cottage Hospital isn’t your average hospital. Located on the small island of Nantucket, Mass., it serves a population of 11,000 permanent residents while balancing a seasonal influx of 50,000 additional visitors. Its 10 inpatient beds and ED provide 90 percent of the services patients require, with transfers to larger facilities made for more specialized care.

It’s also cladded in well-worn wood siding dotted by residential-style window frames and appears more as a sleepy seaside escape than healthcare facility.

However, the outdated infrastructure of the 60-year-old building presents constant challenges to care delivery, inspiring a replacement project currently underway.

The design team at CannonDesign shared an inside look at the planning process and the unique cultural challenges and opportunities presented by the island locale in the educational session “Uncharted Waters: Critical Access 30 Miles at Sea,” presented at the Healthcare Design Expo & Conference held Nov. 10-14 in Orlando, Fla.

Jocelyn Stroupe, director of healthcare interiors at CannonDesign, and Brian McKenna, Boston health region leader at CannonDesign, described how the exterior of the new building will be very similar to that of the existing, guided by a local historic district commission that stipulated, for example, the proportion of residential-style double-hung windows. This affected more than the aesthetic, though, precluding the team from pursuing an original plan to prefabricate exterior panels on the mainland, which resulted in a 20-25 percent cost premium.

In fact, the desire to achieve a modern/contemporary facility within a traditional setting shaped the project in multiple ways, driving the team to figure out how to deliver the familiar. “People are happy with the way things are,” Stroupe said of the island residents.

To that end, the “large house” style uses faux dormers, a sloped room that hides mechanicals, and a one-story ED and ambulatory wings that are built at a low, human scale. The main building is two stories.

The interiors were shaped by the idea of craftsmanship, relying on the island’s Quaker roots that inspire an understated but high-quality aesthetic. The palette includes oak and shades of “sea glass” and “Nantucket fog” blues. And windows that don’t quite make as much sense on the inside as they do on the outside were solved by building out the frames around them to create window seats throughout the corridors.

Additional design elements were incorporated with resiliency in mind, as well, recognizing the island’s location and the difficulties that can arise in accessing it or departing in poor weather conditions. Built to be “the last building standing,” McKenna said, the replacement project includes windows that can withstand winds up to 175 miles per hour and are operable to provide natural ventilation, if needed, as well as system redundancies, mechanicals on the roof, and dedicated sources of electric and water. “This is the place islanders would come to if there was a tragic storm,” McKenna said.

Operationally, the site is designed for flexibility, with a close relationship between the ED and med/surg, where staff will be cross-trained to serve both departments. The interventional suite has a direct line to labor and delivery, while virtual care was considered in the event that weather prevents a patient transfer. An observation room sited across from the nurses’ station is equipped to be a behavioral health room.

The replacement is being constructed on the same site as the original structure, in places just 8 feet apart. The building will be cleared to allow parking for the hospital, what McKenna said should be a quick task for the stick-built structure. The project is expected to be completed in early fall 2018, with the first patient seen by late fall.