renovation of the parliament building in vienna

beletage und bellevue
the parliamentary building today cannot provide the future functions of a citizen-focused house of democracy or contemporary working conditions for parliamentarians within its existing spatial structures. the spatial potential within the existing building is severely limited. areas identified as expansion spaces beneath the two chambers and in the attic barely allow the creation of high-quality, well-lit, and properly accessible rooms. however, an outstanding, previously untapped spatial potential lies in the development of a new roof contour. as a counterpart to the beletage with its magnificent columned hall and the two voluminous chambers, the parliamentary building will be completed with a grand bellevue as a new architectural closure. the existing silhouette of the parliament remains undisturbed; the newly designed volume forms an appropriate conclusion and a balanced backdrop to the sculptural attic ornamentation of the building. the bellevue integrates naturally as a future-proof element within the historical envelope of the parliamentary building. exterior changes remain nearly invisible and only reveal themselves at a distance, especially at night, shining prominently as a confident symbol of democracy and the newly gained transparency of the historic parliament. seemingly weightless, the delicate structure rests atop the central mass of the old building. like an expansive load-bearing surface, the new roof contrasts in form and materiality with the existing structure. the new wing expands and shelters the underlying historic building, which now opens upward. filtered daylight penetrates deep into the columned hall and the two chambers through the new transparent volume. high above the rooftops of vienna, a generous east-facing terrace offers parliamentarians and visitors a spectacular view over the city. the bellevue finds its precise spatial and structural fit on both sides of the columned hall. internal integration of the new building with all parliamentary levels is achieved via generous staircases.

modularity
in principle, the renovation of the historic spatial shells and the expansion of the building in the roof level can be implemented independently and in separate phases. however, it is logical to first develop the potential of the roof landscape through the new construction to relieve the existing volume and to accommodate new technical installations and required escape routes. the historic rooms, including both chambers, can continue to be used while protected from roof-level construction. historically valuable surfaces will remain largely untouched. new technical installations are routed through flanking shafts or the new roof volume. in addition to the newly gained spatial expansions on both bellevue levels, modular potential is available for the expansion of work areas on the third floor along the building’s central axis between the entrance hall and local vi, as well as above the chambers. significant reserves for the future development of the building also exist in the large ground-floor room modules beneath both chambers, where publicly accessible library and archive areas could be optimally arranged, utilizing spatial potential without daylight dependence.

opening of the house
opening the parliament to the public and guiding visitors within the building is of central importance for the house of democracy. the current visitor entrance remains confirmed in location and function. access controls will be significantly expanded to handle future visitor flows without delays. the currently unused areas beneath the columned hall will host central visitor functions, forming the starting point of visitor circulation and the interface with parliamentary work. visitor cafes, shop areas, a democracy workshop, and seminar zones will be established here. the new generous circulation space allows both separation and deliberate interaction of the paths of visitors and parliamentarians.

fire protection
preventive fire protection includes clearing the building structure, removing distances between subsequently inserted uses, and re-establishing independent building sections with manageable areas and volumes. in the newly created areas, modern technical systems achieve a safety level that meets current standards.

fire compartments
compartment sizes are selected according to use and planned technical installations. separation of fire compartments is achieved by constructing new elements, using existing elements with the required fire resistance, or combining structural and technical solutions.

escape routes
escape routes in the existing areas reach a staircase within 40 meters. beyond that, a second escape staircase or an adjacent fire compartment must be accessible. the new roof levels are served by six escape staircases, connecting all floors and leading to an independent exit in the basement. barrier-free access is ensured for mobility-impaired persons. for the roof levels, an evacuation elevator is provided in addition to the fire-fighting lift.

early fire detection
the entire building will be equipped with a fire alarm system to alert occupants in affected areas as quickly as possible and to allow fire-fighting at the onset of a fire, minimizing fire spread.

smoke extraction
smoke from existing uses is primarily vented through openable windows. for the roof levels, defined openings with smoke and heat extraction systems activated via fire detectors are provided.

extinguishing systems/fire-fighting
to limit fire spread, a sprinkler system is installed in the new roof levels and beneath the columned hall. a wet riser system will be available throughout the building for fire-fighting.

integration of new architecture in the historic building
realizing a contemporary, future-proof parliamentary operation without interventions in the historically valuable structure appears impossible. targeted approaches for spatial and structural reorganization are defined. christian kühn stated in “building for democracy” (2011) that adaptations “in the spirit of hansen” would be absurd given today’s requirements in a completely different political and cultural context, advocating for “intelligent and sensitive destruction to create additions at the highest level achievable today.” this “defined destruction” occurs along axes parallel to the columned hall across all floors. existing ancillary and circulation spaces are removed, providing spatial potential for reorganizing the core and accessing future roof levels. the resulting “empty spaces” are painted monochrome white in contrast to the polychrome existing interior. traces of former wall and ceiling connections remain as reliefs, documenting the building’s second renovation phase. the courtyard-facing ends are fully glazed, creating light-filled spaces that mediate between chambers and the columned hall as well as between entry levels and the roof volume.

the only preserved room in the core is the historically valuable speaker’s office, which will be maintained and restored. the apparent loss of historic surfaces is compensated by the newly gained spatial generosity. the previously dense structure can now breathe, revealing unexpected dimensions. new vertical circulation cores are sculpturally placed within the spaces, connecting all levels in a barrier-free manner. the bellevue volume is clearly readable as an additive structure. the rational façade design reflects the internal structural order and functions. façades are either transparent or opaque with insulated panels, depending on internal use. external adjustable aluminum sunshading and photovoltaic elements provide sun protection and sustainable energy generation. the new structure is connected to the existing building only partially for load transfer. internally, the new volume serves as the upper conclusion of the new circulation spines. within the roof volume, two levels host local and gastronomy areas, functionally and spatially optimized. units are free-standing, climate-autonomous modules. generous circulation areas and a large roof terrace offer ample space for communication and relaxation.

national council chamber
the chamber is preserved as an architectural testimony of the postwar reconstruction, maintaining its spatial and material character. precisely placed openings introduce daylight, while two large windows in the rear wall open to the circulation area, allowing visitors to view the chamber. the previously tight corridor volume is expanded to the south façade. the plenary layout is optimized with raised floor plates and barrier-free access. furnishings are modular and quickly adaptable to changing parliamentary groups. visitor gallery inclinations are slightly adjusted for optimal sightlines. the atmosphere reflects a newly interpreted 1950s functional design.

innovative structural engineering
existing roof structures between the middle tracts, between the national council and federal assembly halls, are removed and replaced with a lightweight construction. a high-performance steel-composite structure serves as a load-distributing layer for the existing building and an installation level for technical systems supplying both the underlying building parts and the new volume. existing cross walls can support the new level. the new floor uses trusses supporting trapezoidal profiles carrying high-strength lightweight concrete, resulting in a weight comparable to the previous roof. the actual roof structure is a delicate steel frame, and the second new level is a minimized hollow-core deck.

earthquake load case
the shear-stiff new construction in the middle tract ensures that only the attic areas of side tracts require a horizontally load-distributing deck, raising failure resistance to a standard new-build level.

technical building systems
the existing technical infrastructure is completely revised, establishing clear and transparent structures. existing central systems are largely retained, except for ventilation, while heating and cooling systems are renewed. all mechanically ventilated spaces have defined supply and exhaust air paths with balanced airflows. existing ductwork is repurposed for other media. electrical installations are separated from other systems.

ventilation
two new supply and exhaust units are located on level 3 parallel to the hall rear walls, serving adjacent halls and roof-level locales. air handling in halls remains, locales receive displacement ventilation. adiabatic cooling can assist chillers in summer; winter supply air is humidified. systems are dimensioned for maximum occupancy and CO2-controlled. eastern and western tracts’ units are in roof attics under dual quadrigas with regenerative heat recovery. local vi is supplied from the immediately above attic, with air supplied via long-throw diffusers and extracted via existing wall grilles. gastronomy units have side-placed units with regenerative heat recovery.

heating
existing transformers remain; oil-fired boilers are renewed. the distribution system, valves, and pumps are upgraded for demand-adapted operation. room heating uses static panels with thermostatic valves. floor conduit connections require minimal openings. local vi and new roof-level committee rooms are heated via underfloor systems.

climate cooling
existing main chillers remain; open cooling towers are dismantled. adiabatic cooling in main air handling units relieves chillers; remaining heat is vented along columned hall pylons. hydraulics and control are upgraded.

sanitary
all sanitary supply and disposal systems are rebuilt. central hot water generation serves high-demand areas; remote or sporadic users use decentralized e-storage. high-quality sanitary fixtures and water-saving fittings are selected.

msr
all systems have autonomous substations overseen by a glt system, using only open systems and components. monitoring and long-term data logging are integrated.

electrical engineering
all high- and low-voltage systems, including IT and telephony, are renewed. existing conduits are reused or new ones installed with full respect to historic surfaces. horizontal distribution is mainly at level -1 and the roof structure. sub-distributions are installed in discreet locations. ELT and data connections in local vi and bellevue use floor boxes; other rooms use surface-conserving installations via furniture or skirting. a suitable switch program complements the central building management system.

lighting and emergency lighting
existing historically significant fixtures are adapted and upgraded. newly added fixtures are minimalist and contemporary, contrasting with historic elements. illuminance levels match spatial requirements. energy-efficient lamps and LED technology are used where possible. emergency lighting is brought up to current standards.