BUDAPEST IS ONE OF EUROPE’S GREATEST CITIES, and right in the heart of this historic fabric lies one of the Marriott Hotel’s most beautiful new properties—the Dorothea Hotel—part of Marriott’s Autograph Collection. I was fortunate to stay there this past fall and even more fortunate to have the architects of this incredible complex lead me and others through a detailed tour of the finished project.
Named after the 19th Century Archduchess Maria Dorothea, the hotel honors her influential legacy, particularly in architecture, alongside her husband, Palatine Joseph, who also impacted the city’s history.
The inner courtyard atrium at the Dorothea is wrapped in a modern layer of glass, vertical fins, and balconies, providing a consistent layer that belies the fact that the complex involves three separate perimeter block buildings. (Image: Zsolt Hlinka). (Click on the image for a larger view. Typical.)
The Dorothea Hotel occupies an entire hotel block in the heart of downtown Budapest (technically on the Pest side). It is just a few minutes’ walk from key attractions like the Budapest Christmas Market, Széchenyi Chain Bridge, and St. Stephen’s Basilica. What is fascinating about the hotel complex is that it consists of three separate historic buildings—the MAHART House, The Weber House, and the Münnich House—set as perimeter block buildings with a dazzling center atrium.
The Architectural Challenges
While the Autograph Collection hotels are all singularly unique and special, the Dorothea may have been one of the most technically challenging to accomplish for reasons we’ll explain in detail in a moment. As a five-star hotel line, Marriott delivers a technical specification guide that is well over 1,000 pages long.
The exterior of the Dorothea Hotel block in Budapest. This corner looks at the Web House, built in 1871-73 and was a former bank headquarters. The original lobby columns feature prominently in a bold new interior look (see image at section The Dorothea’s Splendor). (Image: Zsolt Hlinka). (Click on the image for a larger view. Typical.)
To accomplish this marvel, Marriott and the private developer hired Hungarian-based TSPC Group and Milan-based Lissoni & Partners — with the latter responsible for hotel interiors and design direction and the former responsible for architecture, engineering, and construction phase management overseeing the hotel’s complex construction. Naturally, a project of this size and complexity requires a rigorous BIM (Building Information Modeling) process that carries from initial design to construction and handover.
What makes this 35,000-square-meter complex even more demanding is that all three historic perimeter buildings have separate floor levels, and all three were built at different periods in the late 19th and early 20th centuries. Furthermore, these three heritage buildings are precious architectural assets to the city of Budapest, and their restoration as part of this Dorothea Hotel complex adds to the significant ongoing architectural renewal of Budapest in recent years.
Because the Dorothea is a heritage building, there were many things in the specifications that were hard to manage, like the heritage columns, many walls, and the beautiful plaster balustrade system up in the library.
Balancing modern regulations and stringent Marriott standards while preserving the important architectural aspects of heritage buildings requires careful design judgment and technical knowledge.
“Because the Dorothea is a heritage building, there were many things in the specifications that were hard to manage,” says Andrea Tóth-Lovrity, project lead architect for TSPC Group. “like the heritage columns, many walls, and the beautiful plaster balustrade system up in the library.”
The beautiful plaster balustrade in the original Weber House was one challenging aspect TSPC Group had to reconcile against rigorous Marriott standards and regulatory requirements. (Image: Zsolt Hlinka). (Click on the image for a larger view. Typical.)
Tóth-Lovrity explained that the Marriott Standards are impressively comprehensive and cover every imaginable detail that can impact the experience of a hotel guest. In case of the standardized items that could not be fulfilled due to the unique historical nature of the project, Tóth-Lovrity says, “Marriott has either approved and decided that the compromise was acceptable or it had to be rethought to provide the needed claim thereby challenging the design team.” In these cases, TSPC Group would ingeniously deliver alternative solutions.
Challenge – The Levels
Perhaps one of the most interesting aspects of staying at the Dorothea Hotel happens when you enter an elevator. It is there at the button panel that you recognize that the hotel is spread out over three separate buildings, each with unique floor levels. However, the complexity of this reality is certainly lost on the hotel guests.
For the architect and deputy head of BIM at TSPC Group, Károly Bélafi, this complexity still needed to be solved. Tasked with the leadership role of managing the project’s BIM models and construction documents, the Dorothea Hotel needed to be organized like all buildings—by stories (or levels).
A careful view of this total complex BIM model section reveals the various levels problem that the architects had to overcome. The Weber House (left in model) has a much taller 2nd floor (first above ground) than the building across the courtyard atrium. (Click on the image for a larger view. Typical.)
“The Dorothea combines three structures from different eras, each with varying floor heights, so one challenge was presenting these staggered levels on a unified plane,” he says. These planes had to be set at heights where all floors could be displayed without overlapping levels from different structures.” While the overall height of the hotel complex and block is around nine stories high, there are actually 31 different levels throughout the complex.
The Dorothea combines three structures from different eras, each with varying floor heights, so one challenge was presenting these staggered levels on a unified plane.
Achieving this inside a BIM program is hardly trivial, but Bélafi leveraged the properties and features inside Archicad, the TSPC Group’s BIM platform. For each slab at a different level for each story, Bélafi entered a property value that equated to a math function that calculated the difference between one building’s 5th floor, for example, and another building’s 5th floor, to arrive at all proper elevation values for all floors.
This horizontal cut through the entire Dorothea complex and block reveals the complexity of the project and the BIM model. The Weber House is now on the right side of this view. (Click on the image for a larger view. Typical.)
“If I am putting a dimension on a slab in the Münnich building, Archicad can automatically calculate the differences in the levels based on what reference that slab was assigned and on what rules I gave it,” he says. It turned out that Archicad’s flexibility and the way it handled the properties of building objects in the software simplified an otherwise daunting reality.
Challenge – Long Schedule
With a project as complex as the Dorothea Hotel, the overall schedule was going to be longer than usual. Among the three buildings that form the complete block, parts of the complex also include private apartments, plus a presidential suite, three other luxury suites, and a sky bar, all at the roof level.
With this long project duration, shifting programmatic changes, and regulatory updates, the BIM setup became key for managing changes. “Our BIM team has developed processes and solutions based on years of experience,” says Bélafi, “allowing us to adapt to shifting requirements with minimal effort, almost at the push of a button.”
Archicad’s extensible and flexible nature enabled a clever integration with data visualization tools that aided the architects in monitoring progress in the development of the BIM model and documentation. (Click on the image for a larger view. Typical.)
To help advance the project and stay on schedule, Bélafi and his team developed a sophisticated dashboard tool built using Microsoft’s Power Query and Power BI platform to turn data into data visualizations for actionable insights. “We created lists that monitor the model from all relevant aspects,” adds Bélafi, explaining how Archicad can publish data-rich lists in the Excel file format and how Microsoft’s Power Query and Power BI platform can interrogate these files for changes and report updates graphically into a custom dashboard. “The system adds communication, accelerates decision-making, improves focus, and ultimately saves both time and money,” he says.
Advanced BIM
As an integrated firm in architecture, planning, and engineering, TSPC Group is an advanced BIM technology practice, offering capabilities that are not widely common in the industry. The practice utilizes Graphisoft’s Archicad BIM software and is the only Hungarian firm that is a member of Graphisoft’s global Key Clients group.
A section view of the Dorothea complex as seen here in Archicad showing various buildings on and HVAC systems only shown in other buildings. (Click on the image for a larger view. Typical.)
“What’s unique about our company is we have all the different disciplines [of planners] — not just architects — in-house,” says Bélafi, adding that this includes not just structural and MEP engineers but also fire safety planners and interior designers. “It’s great because most other disciplines can have difficulty with BIM model communication [passing BIM model data back and forth between discipline offices], “but because we have them all in-house, we can develop a better workflow.”
In fact, the Dorothea Hotel was the first project at TSPC Group, where the fire safety engineers worked directly inside the BIM model. And speaking of the BIM model created in Archicad, TSPC Group practices full Open BIM workflows so that disciplines can leverage best-of-breed software for their specific tasks. “I don’t feel that real ‘closed BIM’ exists,” adds Bélafi. “There will always be some part of the building that we have to plan that requires a different set of tools.”
27 Discipline Models
With engineering teams and architects working in an ‘Open BIM’ workflow, IFC models were pre-checked by specialists and prepared for clash detection and QA checks. Next, 27 separate discipline models were federated for coordination inside the BIM software Solibri, where rules evaluated the models for checks and tolerances. This process would repeat every two weeks as the design and engineering work evolved.
Along with Archicad, Solibri was used as a BIM model checker throughout the project. (Click on the image for a larger view. Typical.)
For coordination during construction between design and build professionals, the general contractor leveraged Dalux, the world’s fastest BIM viewer technology. The architects also used Graphisoft’s BIMx application. “When we were on site, BIMx was very good for maneuvering through the building,” says Bélafi. However, given the massive size of federating 27 different BIM models, Dalux was sensibly leveraged by team members on laptops and iPads on the construction site, as well.
Whether running on desktop platforms or Apple’s iPadOS, Dalux—the world’s fastest BIM software—was used to federate the entire set of BIM models from all disciplines. (Image: Architosh) (Click on the image for a larger view. Typical.)
Graphisoft, the Hungarian developer of Archicad, was also instrumental in the success of the Dorothea Hotel. According to Bélafi and Andrea Tóth-Lovrity, the project lead architect, when the TSPC Group ran into a critical workflow issue involving a complex IFC process, Graphisoft quickly developed a code change and released it in the next update.
When asked why TSPC Group prefers Archicad as its primary BIM platform, both architects note its flexibility and openness. “It offers many ways to modify its functionality, extend it, or integrate with other software,” says Tóth-Lovrity. An example is how the Hungarian firm worked with Milan-based Lisonni & Partners, where English was the common language between the firms.
I don’t feel that real ‘closed BIM’ exists. There will always be some part of the building that we have to plan that requires a different set of tools.
Leveraging the talent of a BIM specialist who could program in Python, TSPC Group created a Hungarian-English word master look-up list and coded it into the Archicad Saved View settings dialog box. “So this would mean that when we updated a view according to a rule, the view would update all the words according to a customized translation list that compared Hungarian and English words,” says Bélafi. However, since that time, TSPC Group has changed the Python code to integrate ChatGPT directly into Archicad so that the famous AI tool can implement the language translation instead of a manually managed list.
The Dorothea’s Splendor
When you enter the Dorothea Hotel through its primary entrance, you arrive in a stunning lobby with massive stone Doric columns. This heritage section was once part of the lobby of a neo-Renaissance building and headquarters of the United Budapest Capital Savings Bank, constructed in 1873. Stunning artistic portraits by photographer Zoltán Tombor adorn the lobby’s walls while deeply paneled entrances guide the visitor to the hotel’s main desk and lobby waiting area.
The Dorothea’s stunning entrance lobby leaves a lasting impression. (Image: Zsolt Hlinka). (Click on the image for a larger view. Typical.)
Behind the main desk are large compositions of concrete bas-reliefs that reinterpret traditional Hungarian decorative patterns in modern ways. This striking visual contrasts with an equally stunning four-story wall clad in 5,000 blue custom tiles produced by the famous Hungarian manufacturer Zsolnay. Before you even receive your room key card, the visitor is well aware that they are occupying spaces that masterfully blend modern refinements with historical richness. (All images below by Zsolt Hlinka).
Stunning blue Zsolnay tiles on stair tower beyond.
Main desk with Hungarian decorative bas-reliefs.
Historical architecture mixes with modern throughout.
The main tour de force of the Dorothea is the spacious inner courtyard atrium with a massive skylight system atop deep beams clad in dark-stained wood. Nearly all four sides of the atrium feature glass facades and perimeter balconies with vertical fins, the final element of which affords a balance of guest room privacy and in-flux of warm light. The atrium is also filled with living plants—paying respects to Maria Dorothea’s husband, Palatine Joseph, who had a love of botany.
A courtyard-facing hotel room at the Dorothea is decisively modern in feeling with a glass-facade visually connecting to skylight-covered courtyard below. (Image: Zsolt Hlinka). (Click on the image for a larger view. Typical.)
As beautiful as the center atrium is, TSPC Group’s engineers ran advanced computer simulations for the thermal dynamics of the space to prevent overheating in the summer. “Eight different model versions were tested, including solutions combining solar glazing, insulated glazing, passive ventilation, and different shading techniques,” says Tóth-Lovrity. “Analysis showed external shading and insulated glass, along with natural ventilation without mechanical ventilation in the summer, were most effective in both reducing energy consumption and avoiding overheating.” (All images below by Zsolt Hlinka).
A street-facing room embraces historical architectural aspects.
A spa and pool sit at the Dorothea’s lowest level.
The presidential suite features expansive city views.
Praised in the press as the “new pearl of Budapest,” the Dorothea Hotel wouldn’t be complete without gorgeous guest rooms that harmoniously reflect the aesthetic of Piero Lissoni’s major spaces, modulating between more modern and more heritage design motifs. However, what is really masterful about Dorothea is how seamlessly all three heritage buildings work together to create a stunning, unified spatial experience. For this, both Lissoni and Hungary’s TSPC Group deserve immense praise.
