In recent times, nearly every corporate office building in the world has been bitten by the Green bug; energy-efficiency and sustainability are architectural buzzwords and no construction can remain untouched by these all-essential features.

This phenomenon has found its way to India as well, and the best example in recent times is the ACC headquarters in Mumbai. The country’s leading cement company received the LEED India New Construction - Gold rating award for the “Cement House” late last year. ACC received this prestigious award at a specially organized ceremony during the Annual Meet of Indian Green Building Council (IGBC) at the Chennai Trade Centre in Chennai.

Cement House is not a newly constructed building. It is a renovated building, enhanced with multiple features for sustainability and eco-friendliness. Cement House was the first project in the country to be registered under the criterion ‘major renovation of an existing building’. Cement House heralds the legitimacy of the belief that only new constructions can be part of the Green Building brigade.

The building has also received a Five Star rating for being the most energy-efficient in the category of energy-efficient office buildings. This rating has been conferred to it by the Bureau of Energy Efficiency (BEE), Ministry of Power, Government of India.

Central Atrium

The renovation architects unlocked a central shaft in the core of the building to serve as a ready-made grand atrium around which offices on each floor are laid out. The ample use of glass imparts a sense of space by merging the outside world with the interiors. The absence of partition walls, the wide glass windows and a huge central atrium have together facilitated the penetration of natural daylight, making artificial lights redundant for the most day.
 
The asbestos sheet roof has been replaced by a polycarbonate sheet and the atrium has been extended to the basement level for more and more daylight to enter. The atrium is enveloped by glass railings on three sides for maximum transparency and landscaped at the basement level to maximise the green area. The central atrium is equipped with a fire-fighting system as a measure of safety.

A central service core is used to house the HVAC and air-handling units (AHUs) on all floors and run other utilities like the chiller pipes, plumbing and drainage lines, and electrical and data cables. The service core now opens out into the sky-lit atrium. The design of the entire office revolves around the concept of this atrium and allocation of spaces around it.

The existing windows (1,320 × 2,080 mm) with wooden frames have been expanded to 1,320 × 3,000 mm sizes and renovated into more sleek aluminium open-able casement windows using double glazed units (DGU).

Green Roof

Three unused terraces in the building have now been transformed into verdant green roof gardens with plush grass, cobble-stone pathways, flowers, thick foliage and even some palm trees. Native plant species have been chosen as a measure to conserve water. The bright glass windows with these adjacent green terraces offer a refreshing view to the building occupants.

Power Conservation

Optical and motion sensors control the lighting in the workspaces, based on occupancy. Similarly, a new air-conditioning system regulates the flow of cool air depending on ambient temperature and occupancy levels in different areas of the building. The use of solar water heaters together with daylight harvesting and intelligent lighting and control systems help reduce overall energy consumption by 25 per cent.

Water Conservation

Project Orchid cuts down overall water consumption of the building by 50 per cent. All sinks are fitted with sensor-based, water-efficient plumbing fixtures. A sewage treatment plant recycles used water which is then channeled for use in the terrace garden, landscaped areas and water closets. Indoor plants are selected for their low water requirements. Rainwater is harvested effectively.
 
Energy-efficient Materials

Materials selected for use in flooring, ceilings, furniture, wall coverings, carpets, partitions and so on have been chosen for their recycled content or recyclable properties. These are also certified by their respective manufacturers as non-toxic. Similarly, low Volatile Organic Compound (Low VOC) paints, adhesives and sealants have been used to maintain a healthy indoor environment.

Waste Management

Waste will be segregated into dry waste and wet waste; dry waste will be diverted to recycling haulers while wet waste will be further processed to generate organic compost on site.

The open office plan includes modern furniture, well equipped conference halls, meeting rooms and breakout areas on every floor. Each conference room is equipped with the best in telephone conferencing, video-conferencing and overhead projectors. The spacious new canteen with a state-of-the-art kitchen, along with a mini-gym and coffee lounges on every floor further enhance the appeal of the building.