SUSTAINABLE 5/23/2013

Reichstag building The Bundestag, Berlin, Germany

The transformation of the Reichstag is rooted in four related issues: the Bundestag's significance as a democratic

forum, an understanding of history, a commitment to accessibility and a vigorous environmental agenda.

The original Reichstag building is a historical edifice in Berlin Germany, constructed to

house the Imperial Diet (German: Reichstag), of the German Empire. It was completed in

1894. In 1933 it was partly destroyed by fire, and not repaired in the following years, until

even greater destruction at the end of world war II in 1945. However, the massive walls

withstood and survived, while the interior was completely gone. Situated in the west of

Berlin, but with its eastern facade only a few meters from the border (and later the Berlin

wall), it was reconstructed only in 1973, in a simple and temporary way (without the original

copula). Already this reconstruction comprised groundwater wells for direct cooling;

however, the hydrochemistry was not addressed sufficiently, and the re-injection wells were

clogged with iron after a short while, rendering the whole groundwater cooling system

useless.

After the German re-unification in 1991, and the decision to have the capital of the unified

Germany in Berlin, plans to completely refurbish the building were set into effect. Sir

Norman Foster did win the competition of 1992, and in his winning concept already an

aquifer storage for cooling was included. In 1995 the old building became a piece of art,

wrapped by Christo, and after that the whole interior was torn down. While the first deep

drilling for the heat storage went on, it was possible to see the sky through the entrance

portal . The completely renovated building, with a new copula (acting also as a part of the

ventilation system), was inaugurated in 1999.

The design of this work was in the hands of the British architect Sir Norman Foster, and

since the first presentation of his plans in 1992 the energy concept included a geothermal

component, i.e. the storage of thermal energy in the underground.

Location of the buildings of the German Parliament in Berlin (Graphics: Bundesbaugesellschaft Berlin)

The transformation of the Reichstag is rooted in four related issues: the Bundestag's

significance as a democratic forum, an understanding of history, a commitment to

accessibility and a vigorous environmental agenda. As found, the Reichstag was mutilated

by war and insensitive rebuilding. The reconstruction takes cues from the original fabric; the

layers of history were peeled away to reveal striking imprints of the past - stonemason's

marks and Russian graffiti − scars that have been preserved as a 'living museum'. But in

other respects it is a radical departure; within its heavy shell it is light and transparent, its

activities on view.

Public and politicians enter the building together and the public realm continues on the roof

in the terrace restaurant and in the cupola, where ramps lead to an observation platform,

allowing people to ascend symbolically above the heads of their representatives in the

chamber.

Workforce and construction

• More than 25 trade contractors

• 240 workers on site each day during demolition

• Up to 46 people in Fosters’ Berlin office

• Total number of drawings submitted is 1100, presented in 65 folders

• 45,000 tonnes of demolition material removed from the central area of the chamber, in 35

truckloads per day from October 1995 February 1996, using a caterpillar machine with a 43-

metre boom. Altogether, one third of the fabric removed.

• Twelve fairfaced concrete columns in the chamber, each weighing 23 tonnes, carry the

loads of the dome.

Light sculptor (cone)

• Weight: 300 tonnes

• 2.5 metres across at its base, where it punctures the chamber ceiling, widening to 16 metres

• Covered with 360 highly reflective glass mirrors

• A computerised sun-following moveable shield powered by photovoltaic cells, prevents

penetration of solar heat and glare

Cupola

• Height: 23.5 m

• Diameter: 40 m

• Weight: 1200 tonnes

• Steel: 700 tonnes

• Clad in 3000 square metres of laminated safety glass — two layers of glass with an

intermediate layer of vinyl foil - panel size 5.10m x 1.80m max.

• 1.6 metre clear width helical ramp acts as a stiffening ring for the cupola with ramp, cone

and covering integrated into a delicate structural balance, all elements are hung from exterior

structure.

• Observation platform height 40.7 m

The cupola is now an established Berlin landmark. Symbolic of rebirth, it also drives the

building's natural lighting and ventilation strategies. At its core is a 'light sculptor' that

reflects horizon light down into the chamber, while a sun-shield tracks the path of the sun to

block solar gain and glare. As night falls, this process is reversed - the cupola becomes a

beacon on the skyline, signaling the vigor of the German democratic process.

Ecological features

• Natural ventilation in the chamber using fresh air drawn up by the cone through the

chimney effect.

• Heat exchangers recover and reutilize warm air not expelled through the dome.

• ‘Intelligent windows’ comprise manually operated inner layer and security-laminated outer

layer which draws in fresh air via ventilation joints.

• Renewable vegetable bio-fuel burned in a co-generator produces clean electricity, reducing

annual carbon dioxide output by 94 per cent.

• Surplus heat stored in natural aquifer which provides hot water for heating.

• Cold water is stored below ground to provide cooling via chilled ceilings in hot weather.

• Photovoltaic cells cover 300 square meters on south roof.

The building provides a model for sustainability by burning renewable bio-fuel - refined

vegetable oil − in a cogenerator to produce electricity: a system that is far cleaner than

burning fossil fuels. The result is a 94 per cent reduction in carbon dioxide emissions.

Surplus heat is stored as hot water in an aquifer deep below ground and can be pumped up to

heat the building or to drive an absorption cooling plant to produce chilled water.

Significantly, the building's energy requirements are modest enough to allow it to produce

more energy than it consumes and to perform as a mini power station in the new government

quarter.

Sustainability :

Site + Climate

The design utilizes natural light as an architectural feature. Careful attention was paid to the

sun's movement around the building and how this could be used to bring light into the space.

Form + Massing

The renovation project sought to bring light, and openness into the building. To accomplish

this, a large dome shaped sky light was installed to help capture and reflect daylight deep

within the structure.

Passive Design

The solar collector brings natural lighting into the heart of the building, whilst an automated

solar shade protects against unwanted, direct solar gain. The main chamber of parliament is

naturally ventilated via the cupola.

Environmental Systems

The building was designed to optimize the use of passive systems whilst minimizing active

systems. Both the artificial lighting and ventilation are controlled by a central BMS system

and a heat exchanger recovers waste heat from the exhaust air.

Renewable Energy

A biofuel powered, Combined Heat and Power (CHP) provides approximately 80% of the

annual electricity and 90% of the heat load of the building. A large Ground Source Heat

Pump (GSHP) acts as a seasonal store of both heat and colt. Photovoltaic on the roof power

the solar shade within the light sculpture.

Energy Infrastructure

The CHP and GSHP units, at peak operation, provide energy to both the Reichstag and

surrounding government buildings.

Mobility + Connectivity

There are public transport links near to the building and a large number of bike racks for

both staff and visitors.

Materials + Waste

The design aimed to protect and maintain the masonry shell of the heritage building, whilst

redeveloping some of the core areas. By retaining most of the original building structure,

construction and demolition waste was significantly reduced.

Water

Inside the building low flow fixtures and fittings were selected to help reduce the potable

water requirements. All landscaping is either low maintenance or hardscaping, to minimize

water usage.

Land + Ecology

The bio-fuel used to power the CHP unit is derived from locally produced rapeseed

vegetable oil. The Reichstag, next to the River Spree, is surrounded by landscaped areas,

with a mix of biological diversity that is protected and managed.

Culture + Heritage

In stripping back previous reconstruction to the building, striking imprints from the past

were unearthed, including graffiti left by Soviet soldiers. These discoverers influenced the

design, creating a space that sought to become a 'living museum' of German history.

Drawing light into the heart of the building, helped to create an open and visible platform for

the German democratic process.

Wellbeing

The design sought to bring light and fresh air into the heart of the Reichstag, improving user

wellbeing. The addition of viewing galleries and breakout spaces have brought additional

amenities to the building.

Prosperity

The use of a locally produced biodiesel has helped protect and enhance the local agricultural

economy. Increased tourist numbers to the Reichstag, has bought added benefits to the

immediate vicinity.

Planning for Change

Creating a building that was open and honest about it's past has helped it become open-

minded and forward-thinking about its future. The Reichstag has now become a beacon,

signalling the vigour of the German democratic process.

Performance in Use

The operational energy profile for The Reichstag, shows that it uses 57% less primary

energy than typical existing buildings, and 39% less than the requirements for new

buildings.

References :

- http://www.constructalia.com/english/case_studies/germany/transformation_of_the_reichstag_new_germ

an_parliament

- http://sanner-geo.de/media/1438.pdf

- http://www.fosterandpartners.com/projects/reichstag-new-german-parliament/

- http://www.bundestag.de/htdocs_e/visits/besgrupp/flyer_2012.pdf

- http://en.wikipedia.org/wiki/Reichstag_building