The headquarter of the Bellona Foundation, Oslo

Project description

The Bellona House fulfills Energy Class A requirements. The building was completed in December 2010 and consists of offices, businesses and restaurants.

When Bellona initiated its cooperation with developer Aspelin Ramm in 2008, the vision was to build as energy effectively as possible within commercial limits. In the autumn of 2009 the developer committed to following FutureBuilt´s quality criteria with the requirements of reducing greenhouse gas emissions from energy use, transport and material use. In the process, ambitions were extended to apply to the building´s general climate profile. Everything from material selection to life cycle analysis was thoroughly examined. A mobility plan for the whole Vulkan area was established.

The most striking aspect of the building is its sawtooth-shaped south facade, where the glazed surfaces face downwards and are shielded from excess solar gain by solar panels on the upper surface. The architecture makes the most use of the sun´s heat in a functional way, at the same time as the sun´s exposure on the windows is limited despite the large south-facing glass surfaces.

The developer focused on multi-disciplinary cooperation from the project´s outset, and emphasized energy design and energy calculations throughout the planning process. An external and independent energy consultant has followed the project from drawing board to completion.

Low carbon strategies

The property is centrally located in Oslo and is easily accessed by public transport. Nearby are buses with regular departures, and a new bridge over the Aker River connects the Vulkan area with Grünerløkka in the east. Bellona´s employees do not have access to parking within the building.

The heating requirements of the building are very low as a result of good insulation (roof 400mm, walls 270mm), good windows (U-value 0.8), minimal cold bridges and a low air leakage factor (0.5 to 1.0). An extremely good ventilation heat recovery system (efficiency 87.6 per  cent) was also installed. The cooling needs are reduced through a low window area, good external sunscreening (automatic blinds) and angled windows on the south facade that provide indirect solar shading. The building also has 50 per cent exposed concrete ceilings that accumulate heat and regulate the temperature throughout the day, as well as cool it at night. An energy-effective lighting system (3.8 W/m²) was installed and is demand-controlled in the office area.

The local energy centre supplies the building with heat, cooling and warm water. This centre gets its energy from the solar panels installed on the roof of Bellona House, a local ground source heat pump and district heating from Hafslund at peak load.

The building´s primary structure is conventional concrete, which results in significant greenhouse gas emissions from the foundations, external walls and roofs. Some of the façades have rendered cladding panels made from recycled glass, while on the north façade the render is put directly on the insulation. The south façade uses normal, insulated wood studwork, while the west and east façades use Iso3 studwork from Moelven. The choice of wooden windows with external aluminum cladding to limit maintenance was a compromise. To minimize greenhouse gas emissions the use of aluminum was kept to a minimum on the rest of the building. The floor surfaces consist of cork linoleum, which was chosen for its environmental credentials.

Key Figures

Project Information