Pahala, Bhubaneswar, Odisha | February 2020
Residential Rooftop Ecosystem
Every journey begins with a single experiment.
For CHAAS, that experiment started on a fourth-floor rooftop in Pahala, Bhubaneswar. The homeowner, Sisir—a scientist associated with CSIR and an avid gardening enthusiast—shared a simple vision: could a rooftop become cooler, greener and more comfortable to live in?
At that time, rooftop gardening was still a new concept in Odisha. Lightweight construction systems, specialised growing media and efficient irrigation methods were largely unexplored. Instead of following conventional practices, we decided to experiment.
To reduce structural load, we used AAC blocks instead of traditional bricks. The planting areas were developed using a soil-based growing medium, which later evolved into lighter compost and cocopeat mixes as we continued learning. The rooftop featured ornamental plants such as Eugenia, Thuja, Adenium and Mexican Grass, selected for their ability to withstand rooftop conditions.
As the project matured, the irrigation system also evolved—from conventional sprinklers to more efficient drip irrigation, reducing water consumption while improving plant health.
Years later, the rooftop has survived two major cyclones, with more than 80% of the original planting still thriving. The homeowner also observed a noticeable reduction in rooftop heat, demonstrating the potential of living landscapes to improve thermal comfort.
Looking back, this was never just our first rooftop garden.
It became the foundation of everything we know today. Many of the ideas we now recommend to clients—lightweight systems, improved irrigation, better growing media and climate-responsive planting—were first tested here.
Every innovation begins with the courage to experiment.