The revolutionary concept of vertical integration that first allowed hospitals to stack the patient bed tower above the diagnostic and treatment base opened the door to a new paradigm of hospital organization.

Over the course of history, the developments in vertical transportation, beginning with Otis’s invention of the first “safe” elevator in 1853, may have brought about new possibilities for a more free organization of the ground floor plan, but the concurrent success of new procedures triggered the increasing complexity of the diagnostic and treatment (D&T) base.

While the ability to exploit the vertical dimension has the potential to reduce both travel distances and building footprints, as large urban hospitals moved away from sprawling courtyard plans like St. Thomas's Hospital in London (1871), the watershed moment in hospital planning was tempered by simultaneous advances in surgical procedures.

Early in the 20th century, the development of the X-ray and anesthesia had a great impact on the hospital form, as the increasingly central role of equipment and machinery necessitated expanded diagnostic and treatment areas (Fang, 2000). In the 1950s, several departments increased in size (e.g., surgery with clean cores, radiology with dedicated modality suites, and the emergency department with multiple “pod” clusters,) while in the 1960s, there developed a need for critical departmental adjacencies (e.g., emergency and radiology, labor/delivery and C-section ORs).

Thus, what we saw in the 1950s and 1960s was a shrinking of the bed floors and the enlarging of the D&T base. By the early 1970s, with new departments emerging (e.g., endoscopy), the ever-growing diagnostic and treatment departments, and desired adjacencies had forced the D&T base to become even larger and spread out.

The need for critical access and horizontal adjacencies to support these quickly evolving specialties resulted in labyrinthine floor plates filled with medically intense and frequently windowless spaces. Furthermore, the almost inevitable additions to these buildings compromised wayfinding and often eliminated the quantity and clarity of adjacent open space.

Many of these hospital designs are still all around us and, while they function from a basic medical operations point of view, are often disappointing in terms of scale, character, integrated open space, and, most importantly, the patient and staff experience. With an understanding of the potential benefits gleaned from vertical integration, a reconsideration of the bed tower on a D&T base seems overdue.

Two recent hospital designs take on the paradigm. Informed by a Corbusian tenet, these urban hospitals reclaim the considerable ground area lost by the diagnostic and treatment base, and transform it into expansive rooftop gardens that serve the entire campus (see images in gallery).

A hospital in a garden
The design of the new 1.5-million-square-foot, 900-patient-bed Jurong General Hospital in the Republic of Singapore required defining two major architectural moves: organizing the bed/clinical towers in a linear fashion to optimize open space and access, as well as the decision to build the main garden over the D&T base.

Jurong General Hospital’s site is bisected by a public road and resides in an urban mixed-use area of large-scale retail, mid-rise commercial, and high-rise residential buildings. The large program, natural ventilation requirements, height and lot coverage restrictions, and a client-driven focus on gardens were major forces that shaped the design solution.

Organizing the clinical bed towers
The simple systems of organization and circulation serve to offset the considerable size of the program. With the programmatic elements arranged as a series of semi-independent buildings placed end to end, simple racetrack corridors replace the maze-like paths often found in such complex facilities.

Distinct lobbies and vertical cores lead patients, visitors, and staff through a logical circulation system. Landmark-type elements such as gardens, the food court, and the administration tower serve as intuitive reference points for wayfinding in the rational plan.

Despite the horizontal appearance of the hospital center, the strength and simplicity of the circulation system relies on a vertical approach.

Two important objectives were met by building the garden over the D&T base: (1) satisfying the client's desire for a garden-like environment and (2) accommodating the large diagnostic and treatment floor plates while still complying with lot-coverage regulations. Raising the park-like garden from the street on a bermed platform removes it from the activity of the busy urban streetscape while allowing discreet access for emergency vehicles to enter the ground floor of the hospital.

The hospital's garden accessibility and integration with the building—along with the climate of Singapore—will help foster the concept of a "hospital without walls" and will serve as an amenity for both the hospital and the community. The garden accommodates a multitude of functions, including rehabilitation, relaxation and contemplation, gardening, recreation and education, and visual amenity.

The elevation of the main garden level provides a connection to the city's pedestrian bridge network for seamless movement to and through the site. The clinical/bed tower, which presides above the garden, is perforated by a network of hanging gardens offering more targeted and private healing zones.

Similarly, the main garden level is perforated with smaller "sunken gardens" allowing natural light to penetrate into the functional spaces of the two-level D&T base. The ground level of the base, within the bermed plinth, is dedicated to lobbies, amenities (including an open air food court), and the emergency department.

The Celler-1 level is below grade, housing operating theaters, day surgery, diagnostics, and support spaces due to the minimal need for exterior exposure. The entire complex is serviced by a light-vehicular racetrack system with service elevators and discrete access points for vertical connections to the tower.

The ideas explored at Jurong General Hospital demonstrate a new approach to accessibility and functionality of the D&T platform, providing more open green space than a conventional solution and effectively re-casting the clinical/bed tower as a “hospital in the park.”

The unifying element
The design of the new 3-million-square-foot, 850-bed Sheikh Khalifa Medical City in Abu Dhabi presented an opportunity to build upon the ideas explored for Jurong General. Here, the diagnostic and treatment base would be the unifying element in a campus that includes three hospitals: General, Women's, and Pediatrics.

Conceived as a "city within the city,” this new medical facility will be ideally situated in central Abu Dhabi, where it will rise on the existing hospital's 90-acre superblock. The exceptionally large program, interior block location, height restrictions, and integration of three hospitals under one roof drove the design solution.

Two landscaped entry drives extend the city grid to the new facility at the super block's interior. At the convergence of these two entry axes, a major public interior space is created, the “town center.” This multi-leveled place of exchange includes lobbies, shops, cafes, education spaces, prayer rooms, and light-filled courtyards.

As the vibrant heart of the campus, it is embedded within the D&T base, offering a welcome respite to patients
, visitors, and staff. The heavily programmed base is home to a wide array of medical services from outpatient clinics to day surgery, the emergency department, radiology, operating theaters, ICUs, NICUs, PICUs, and labor and delivery.

The bed towers rise above this two-story diagnostic and treatment base while giving unique expression to the General, Women's, and Pediatric hospitals. The entire assembly—bed towers, D&T base, and the below-grade support levels—is all vertically integrated for the convenience of patients, visitors, and staff. On the service level, a below-grade loading dock connects to a light-vehicular racetrack that accesses the service core—ensuring discreet back-of-house operation.

The common
On the roof of the diagnostic and treatment base, just above the town center, is "the common,” a shaded oasis that will offer patients, their families, and other visitors a generous outdoor space for relaxation and quiet contemplation. Envisioned as an extension of the public realm, it is accessible from the hospital interior or directly from grand stairs at the General and Women's hospitals entry courts.

The common and the other adjacent rooftop gardens comprise a total of 5.5 acres of centrally located public green space, activated by cafes and other indoor amenities. Along the main promenade, small cabana-like structures create intimately scaled interaction and relaxation nodes among rows of date palms, while a water feature animates the space through sight and sound.

A play area for the Pediatrics Hospital creates a welcome diversion for young patients and their families, while a private garden allows patients to embark on their rehabilitation routines in the open air for much of the year. Beyond the active engagement of the garden level, this landscaped roof serves as a visual amenity for the many patient rooms that look down upon it.

Like Jurong, the rooftop garden is also perforated by a series of courtyards that draw light and nature down into the expansive floor plates of the diagnostic and treatment platform. These courtyards and healing gardens organize program modules and will assist in wayfinding. Unlike Jurong, however, the face of the D&T platform is not concealed behind a landscaped berm but instead is exposed to bring natural light to perimeter clinical spaces within.

At the center of a campus superblock, the design of the Sheikh Khalifa Medical City creates a protected, centralized campus that is green at its very heart. By conceiving of the roof of the two-story platform as an extension of the landscape and the larger public realm, its shaded oasis will engage adjacent amenity spaces to form a bustling indoor/outdoor environment and help create a dynamic, campus-like atmosphere that few urban medical centers enjoy.

Given the inevitable demand to expand medical facilities, a master planning approach with a built-in safeguard to protect and preserve open space is certainly prudent. In Le Corbusier's "Five Points towards a New Architecture" (1926), he recognized the potential of roof gardens to recapture the open space lost by a building's footprint. Casting the roof of the diagnostic and treatment base as a campus common can realize this idea on a grand scale.

Additionally, it can maintain a coherent, integrated, and vital character to that open space through a sustainable strategy. The D&T base, the long notorious space hog of healthcare lot coverage, can, ironically, be the solution for this medical campus planning challenge.

Scott Habjan, AIA, is an Associate Director and Senior Designer for the Health+Science studio at Skidmore, Owings & Merrill in New York. He can be reached at