OREANDA-NEWS. December 27, 2012. KBC has marked 12-12-12 with the opening of its first energy-neutral branch in Belgium. It is an 'active building' in that it is fully self-sufficient and generates all of the energy it needs. The new bank branch is located on the Edingsesteenweg in Leerbeek, part of the municipality of Gooik in the Belgian province of Flemish Brabant. The project is part of KBC's corporate social responsibility initiatives. With it, KBC wants to show that a modern bank branch and sustainability can go hand in hand. Through its construction and renovation projects, KBC is striving to continue making a lasting investment in reducing its ecological footprint while providing staff with a comfortable place to work. The building was designed by the architects Goedefroo+Goedefroo. They were tasked with developing a low-energy building that also fully meets the requirements of a modern bank branch.

Sustainable building techniques and materials for top E (energy performance) and K-value (insulation) ratings.

Use of natural energy sources, recycled and light materials and the ability to use available space flexibly is central to the project. Very high insulation and quality standards were also adopted.

The branch runs entirely on green energy, 80% of which is generated on-site using geothermic systems and solar panels. This gives the building an energy performance or E rating (how energy-efficient a building and its permanent systems are in normal circumstances) of 1.

The new branch also features geothermic systems that both heat and cool the building using an underground energy storage system consisting of ten, 60-metre boreholes. Heating is provided by a heat pump that supplies hot water for the underfloor heating system. The building is air- conditioned using water cooled underground, so free-cooling can be achieved through concrete core activation. This involves pumping cold water around piping in the concrete ceiling, removing the need for a cooling unit.

The building is also fully insulated. The floors and roof have a 20 cm insulation layer. The wall insulation is 15 cm thick.

The triple-glazing ensures a heat loss coefficient which is about half that of traditional double glazing. The K-value measures the total thermal conductivity of the building. The lower the K- value, the better insulated the building is. The branch in Leerbeek has a K-value of 25 (the permitted maximum since January 2012 is 40).

Sustainable materials used

Concrete, glass and aluminium are the main materials used in the construction of the energy- neutral branch. Polished concrete prefab walls have kept the use of other materials to a minimum, so materials like facing bricks and plaster weren't needed. The aluminium sections have high-grade thermal insulation, are maintenance friendly and will last a long time.

Cradle-to-Cradle fittings and furniture

Cradle to Cradle (C2C) is a new way of thinking about sustainability. It involves developing products in such a way that they are environmentally friendly, safe and reusable from beginning

to end. Essentially it means that, once materials used have reached the end of their lifecycle in one product, they are then used beneficially in another. They may not lose their quality and must be reusable. KBC uses Cradle-to-Cradle fittings (wall cladding and gypsum plasterboard sheets) and furnishings.

Rainwater

To save on and prevent wastage of drinking water, a 20 000 litre underground tank collects rainwater, providing enough water for toilet flushes, garden maintenance and cleaning throughout the year.

Maintenance-friendly landscaping

The gardens are being landscaped with sun shade in mind and will require minimum maintenance. Ground-cover planting has been used instead of lawns and KBC has opted for indigenous willows native to the area.

Energy-efficient construction methods and materials used through close co-operation between the contractor and architect.

The branch's concrete walls were prefabricated to size using custom-made frames then fitted on-site. This meant less transport was needed to and from the site and the frame of the building was in place in just two months.

After the tender period, KBC and the architects decided to work with just one general contractor. This meant a single contact on-site, less meetings and travel and a shorter turnaround time. It was also agreed with the architects that as little paper as possible would be used, so all information, plans, paperwork and quotes were exchanged digitally.

Price tag

The branch cost no more than 8% more than it would to build a traditional one. Depending on how energy prices develop, the extra cost will be recouped in the medium term through the reduced energy consumption and efficient maintenance of the building.