Architects banking on building code to resolve green issues
Building Design and Construction – 25th Jan 2009
Office workers and visitors taking the lifts and escalators to work each day at the ICC are part of a towering commitment to ensure buildings become more environmentally friendly.
Buildings account for a massive chunk of heating, cooling costs and harmful carbon emissions, but architects are continually striving to enhance energy-saving features and reduce their carbon footprint.
Mega-skyscrapers such as the ICC can propel these aims further while improving the quality of the surrounding environment – particularly in densely populated Hong Kong. Cass Gilbert, one of the architects who pioneered the New York skyscraper boom in the 1920s, described such towers as machines for making the land pay. Today, leading local architects such as Rocco Yim point out that tall buildings take the corporate world up where it belongs to allow more ground space to be used for recreation or leisure. Or that is the theory. What Hong Kong has seen in certain areas is the “wall effect” whereby tower blocks have been built in a row, often upon a four- to five-storey podium housing car parks or shops. This has been blamed by environmentalists for causing overheating on the ground below.
Architects and planners hope these issues will be resolved when Hong Kong’s first Green Building Council is established. The council will implement a new building code designed to give a more accurate labelling to a development’s environmental features, which will take into account density and the heating effect a building has on the surrounding area.
By its completion next year, the ICC’s environmental standards will have been benchmarked against the best US and European buildings. It has an estimated 100 advanced green features, even as construction continues on the upper floors.
Sun Hung Kai’s project management department set a target of achieving the platinum standard set by the Hong Kong Building Environmental Assessment Method Society. Studies were made using computational fluid dynamic models into the effects that a new microclimate would have on the neighbourhood. Hazards ranged from downdrafts and the reflection of sunlight to noise pollution, heat build-up and the discharge from cooling towers.
Exhaustive tests were carried out to decide where to locate wind deflectors to combat the effects of downdraft. The likely flow and impact of cooling tower emissions were also analysed to minimise the effect of any pollutants and to avoid creating a heat island, particularly in the “dragon’s tail” area of the site leading towards the Elements shopping mall. Each aspect of design, construction, operations, maintenance and property management had been studied, including the illumination of the building façade to mitigate the intensity of light facing residential buildings.
Inside, condensed water from the ICC’s air-conditioning system is reused twice: first recycled through the main cooling towers and then used to flush toilets.
Double-glazed curtain walls with low-emittance coating ensure good thermal insulation while major mechanical and electrical systems are equipped with power analysers. This would enable energy audits to detect which parts of the building consumed the most power and identify where energy saving could be made.