Open-heart surgery

When brain surgery is scheduled at short notice, the jackhammer falls silent. The excavators stand still. The construction crew moves on for the time being. Construction can continue elsewhere on the extensive hospital grounds. Situations like these make it clear under what conditions the Klinikum Stuttgart is currently being rebuilt. Demolition, excavation, planning, and new construction are taking place on the inner-city hospital campus. At the same time, the emergency room, operating theaters, children's hospital, radiotherapy, cancer center, and numerous other medical areas continue to operate.

Vibrations, dust, or noise are therefore not just the usual side effects of a construction site. They can directly impair hospital operations. And this must be avoided as much as possible, emphasizes Öner Tiryaki: "Operations must continue. That is our overriding priority. We cannot say, now there will be a construction site here for years and therefore no hospital operations will take place." The BIM expert has been working at Klinikum Stuttgart since September 2025. There, together with a colleague and the entire new construction team, he is advancing the previously initiated BIM strategy and increasingly aligning it with later building operations.

A hospital is not an office building

The renovation and new construction of Klinikum Stuttgart is currently the largest construction project in the state capital of Stuttgart. Around 1.28 billion euros are earmarked for it until its expected completion in 2033. The project aims to create the buildings and organisational foundations needed for future hospital care - with a focus on top-tier medical care, process optimization, economic efficiency, and patient-centred care. The project is organized by the hospital's own Construction and Engineering Service Center (SC-BE), which also acts as the client. More than a hundred employees coordinate planning, construction, and the requirements of later operation.

The current construction phase shows what this means in practice. A multi-story existing building is dismantled, and then a new hospital complex is built in its place. The excavation pit reaches a depth of about twelve to fourteen meters, and about 40,000 cubic meters of material must be excavated. Among other things, a new emergency room and another helipad are to be built here. Only when this area is completed can the next part of the building be dismantled. Departments relocate, and new links have to connect to existing hospital buildings. The renovation therefore does not consist of a clear before and after, but of a long sequence of interdependent intermediate states.

Klinikum Stuttgart

Patient care comes first

Normally, the construction schedule determines when which work takes place. On a hospital campus, this only works to a limited extent. If noisy and vibration-intensive work is scheduled, it must be coordinated with medical operations. Certain activities can therefore only take place outside normal surgical operating hours or on weekends. Nevertheless, the project must progress. These dependencies actually make the redevelopment comparable to open-heart surgery: a complex system is changed while it must function continuously.

The concentration of technical systems adds further complexity. In an operating room, an intensive care unit, or a highly technical examination room, architecture, structural framework, ventilation, electrical systems, medical technology, fire protection, and numerous other systems come together in a confined space. At the same time, medical workflows determine where equipment may be placed, how much movement space is required, and which connections must be available at which position.

28 sub-models for a new hospital building

In the new building, the hospital therefore consistently relies on model-based planning. The total of 28 sub-models of the project show how great the technical complexity has become. The architecture alone consists of several models. Building services engineering, for example, is also divided into ventilation, heating, electrical, and other areas. Medical technology adds additional models.

BIM initially takes on classic tasks: specialist planning is coordinated, spatial conflicts are checked, recesses and openings are coordinated, and quantities for tenders are validated. However, the actual ambition goes further. The model should not have fulfilled its purpose with the completion of the building, but should become the basis for later operation.

Klinikum Stuttgart

Doctors, nurses, building engineering, medical engineering, facility management, and other departments are therefore also involved. Their questions differ significantly from those of architects and engineers, says Tiryaki. "A doctor, for example, is interested in whether circulation space are sufficient for the later medical workflow. Medical technology checks whether a device is correctly positioned, whether connections are available, and whether valves or power supply are in the required position. Nurses can say from experience where a soap dispenser must be mounted and how circulation routes should be arranged. Facility management, in turn, is interested in materials and surfaces because they affect cleaning and operation."

All these people review the same design from different perspectives. The Construction and Engineering Service Center therefore also acts as a facilitator. Information must be collected, evaluated, and passed on to the right place. The model thus becomes a common basis for discussion and a central information pool.

From BIM to BIM2FM

The strategic goal is BIM2FM. Information generated in planning and execution should then be reused in facility management. "The question quickly arose: What information does the operator actually need later?" says Tiryaki. "The first answer is often: all of it. But on closer inspection, that doesn't work." Because every additional piece of information must be generated, checked, transferred, and kept up-to-date permanently. The hospital is therefore deliberately limiting the amount of data it collects.

Attribute lists are created for different types of components, defining which information is actually necessary. Tiryaki estimates that around 40,000 properties currently need to be managed across the project. This number should not grow further; on the contrary, it should become smaller. The team needs to find out what information the respective user really needs. This verification process is currently underway and should already benefit from the experience of the first construction phase in the next one.

Above all, it's about efficient workflows. What this can mean in everyday life can be explained using an inconspicuous component. A fire damper reports a malfunction. The search for information then begins: Which damper is it exactly? Which system does it belong to? What documents are available for it? When was it last serviced? What inspection is due? Is there a diagram of the system? Some of this information is already available digitally, other data is still stuck in documentation and folder structures. In the worst case, a technician can spend hours just establishing the full context of the problem.

Tiryaki describes the future approach: "Every relevant component gets a unique identifier. A technician can access the associated information directly via a device number or a QR code." The goal is a networked information landscape. Part of the data is directly embedded in the model, other information is stored in databases or connected documentation systems. Tiryaki takes a pragmatic view of the proportions involved: Around 60 percent could be conveyed directly through the model. Together with databases, the long-term aim is to make around 90 percent of the information needed for operations available digitally. The remaining ten percent also reflects the continuing need for human checks.

Many departments need open standards

For this approach, the hospital needs systems that can exchange information with each other. IFC is intended to ensure that building data is not exclusively tied to a specific software. BCF is also used for communication about planning problems. The open exchange format makes it possible to provide specific locations in the BIM model with comments, responsibilities, and issue status, without having to send the entire model each time.

IDS, a buildingSMART standard for the machine-readable definition and checking of information requirements, is also already being partially tested for quality assurance. This reflects the reality of a large hospital: On such a campus, many departments work with different software solutions. A single application will hardly completely replace this landscape.

Before the model can support operations, it needs to be checked against reality. A planning model shows how a building should be built. Operations, however, needs information about how it was actually built. Between the two lie years of construction, during which pipes may have been moved, solutions adjusted on site, and construction details changed. The hospital therefore relies on an as-built model, which is intended to document the actual state. This involves 3D scans and point clouds. The scan data is then compared with the models. Only from this does a reliable basis for facility management emerge.

This process does not end after commissioning. If rooms are later remodeled or technical systems are changed, the digital information must also be updated. The as-built model is therefore not a frozen final state, but a starting point for ongoing digital building operation.

Digital and organizational change process

Not everyone immediately sees an advantage in changing existing processes. The transformation is therefore not only a digital but also an organizational change process, emphasizes Tiryaki: "Interestingly, doctors and nurses were sometimes more receptive to the model than long-established specialists. Those with little experience with construction plans quickly recognize an immediate benefit in the 3D model. Those who have been working with established tools for years need to be more convinced that the new way of working will save time in the long run."

The project team therefore relied heavily on communication. At times, several presentations per week took place with different departments. Again and again, it was explained what goal was being pursued and what practical benefits each group could gain: less searching, less carrying documents around, finding information faster. At the same time, the project needed the backing of the hospital management.

Efficiency as a hard metric

When the new building goes into operation around 2030, the next phase begins. Then, for the first time in everyday life, it will become clear which information is really needed, which processes work, and where the concept still needs to be refined. The findings will then directly feed into the next construction phase. Later, an even bigger task awaits: The existing campus is also to be gradually digitally recorded. Unlike a new build, no BIM models are maintained there from the outset. The existing buildings must first be surveyed and their information structured. At the same time, they are constantly changing due to renovations. Tiryaki describes this step as the ultimate challenge.

The success of the project is measured in hard figures. After about a year, there should be enough evidence for the first reliable assessment of how the new processes perform in practice. This makes 2031 an important milestone for evaluation. Then, the hospital will look at efficiency, maintenance costs, and workload, among other things. Only then can it be assessed whether the considerable effort for data structures, models, software, and organizational change actually brings measurable benefits. Until then, the team is deliberately treating much of the work as a learning process. "Just do it," is one of the pragmatic working rules that Tiryaki describes for the project.

What other hospitals can learn from this

And perhaps replicate it. The lessons should benefit more than just the Stuttgart site. The hospital is a member of buildingSMART Germany and works, among other things, in the Hospital Construction expert group. There, hospitals, planners, and other specialists exchange ideas about common requirements. One topic is also the question of which attributes hospital operators actually need.

Instead of each hospital developing its own lists and data structures, common foundations could emerge from this in the long term. The hospital brings its experiences from the current project into this discussion. Precisely because there are currently hardly any blueprints for an end-to-end BIM2FM process on a hospital campus of this magnitude, this exchange is of particular importance for the project. The transformation of the Stuttgart Hospital is therefore comparable to open-heart surgery in two respects: While medical operations continue, the hospital is not only remodeling its buildings. It is simultaneously changing the way these buildings could be planned, documented, and operated in the future.