Chadwick International designs sustainable office building for challenging climate
Commissioned by Xchanging plc, a UK-based global outsourcer with a large footprint in India, Chadwick International's task was to provide an economic office in Shimoga which would attract the talented youngsters coming out of universities and colleges in the region and, most importantly, would help retain them. The office design needed to be sufficient to accommodate up to 1000 staff initially and 2000 over a five year period. The architects were required to create a platform that is modern, open and interactive. In addition, the client did not want to lose staff, so the solution had to be clever to attract and retain clever staff.
The design was also required to take advantage of the tax breaks and other benefits arising from investment in the Special Economic Zone set up in Shimoga by the Karnataka government, as well as adopting low carbon best practice in the design of the building.
The building needed to be inexpensive. Air conditioning was the obvious big ticket item to lose as it typically accounts for 40% of capital cost and 25% of running cost. The architects worked with Buro Happold to design a naturally ventilated, deep plan building that not only supported modern interactive working practice but provided acceptable environmental conditions in a tropical monsoon climate. The combined concept building has been executed on the ground by Venkatramanan Associates, one of India's larger architectural practices.
An ‘Integrated Solution Roof' includes large wind-catchers which are orientated towards the wind. The shading pattern is formed by the passage of the sun throughout the day and the year. The roof creates a pressure differential which draws fresh air in, while protecting the facade from all direct solar impact. The facade itself features an optimised glazing area for maximum day lighting and large vent areas allowing optimal natural ventilation.
The structure comprises mushroom capitals achieving the widest spans and creating open space, as well as exposed concrete to use the positive effects of high thermal mass. Two 15m wide floor plates (north and south) are separated by an atrium which rises above them. The stack effect draws fresh air in and blows stale air out. The cores accommodate all services, bookended to the east and west with solid elevations, offering protection from low sun angles in the morning and evening.
The site plan is orientated towards the sun and the prevailing winds. Green landscaping around the building avoids heat islands, while water features cool the air entering the building. There is low vegetation to the north and south of the building, with higher vegetation on the east and west sides guides the winds.
As a consequence of the integrated design process between architect and engineer this building is singular; a modern, deep plan, interactive and environmentally friendly workplace in a challenging climate.
The savings on capital and running costs of the building compared with an air-conditioned equivalent are significant. The architects have received an initial reaction that suggests good levels of occupant satisfaction, attendance and high productivity.
The optimum building design has been developed to achieve the best comfort levels for inhabitants possible. Temperatures can reach 40°C in Shimoga and the building is designed to perform well passively in these conditions.
It is now practically complete and occupied on the ground and first floors. Completion of second and roof is underway, as is the landscaping. Final completion is expected by March 2013.