Telangana has a lot more to be done in affordable housing, says Center for Science and Environment (CSE)’s pilot assessment. Telangana’s Dignity Housing Scheme says that it meets some of the thermal comfort requirements, but not all.
CSE’s assessment report – Guidelines for Affordable Housing in Telangana — released by Telangana’s Special Chief Secretary Arvind Kumar, in a meeting organised jointly by CSE and Administrative Staff College, Hyderabad.
Along with building design, it suggests the need to pay attention to the layout plan of building clusters. It found that a single building block may show 38 per cent day-lit areas, but in a cluster this may drop drastically to 7 per cent due to shadow from other buildings.
Due to tunneling effects in a building cluster nearly 60 per cent of the blocks in the project areas are either too windy or are in wind shadow areas compromising ventilation. Most sites are not meeting the regulatory benchmark for heat gain through the exposed and unshaded walls and heating up, it added.
CSE felt it is possible to reduce heat gain by tweaking the orientation of the buildings and adopting appropriate walling material to prevent heat ingress. Just by combining appropriate design and walling material it is possible to increase annual thermally comfortable hours compared to conventional material and design by upto over 330 hours. This reduces the requirement of energy intensive mechanical cooling.
Most affordable housing projects are in the city periphery and have poor access to essential services like transport, schools, health care. If not addressed this can increase the cost of living for the occupiers and compromise sustained occupancy.
CSE said there is a need for urgent adoption of guidelines, mandate and fiscal strategy to improve building design, material, layout plans and decentralized services for thermal comfort and liveability of mass housing projects.
“This assessment has underscored the importance of integrating thermal comfort requirements when real estate recovery is expected to add millions of dwelling units to the formal housing stock in the next three-four years in the country. Otherwise, the new infrastructure can lock in enormous energy and resources guzzling when India has to meet an ambitious target of billion tonne of carbon reduction by 2030 for climate mitigation,” says Anumita Roychowdhury, executive director, research and advocacy at CSE.
In fact, India’s Cooling Action Plan (ICAP) has projected the cooling demand to increase 11 times in buildings between 2017-18 and 2037-38.
CSE observed that ventilation is influenced by the form, height, distance between buildings, clustering, and placement of blocks on the site. It was found that 60 percent of buildings in targeted projects were either in wind shadow areas not receiving adequate air exchange while others were too windy. It is therefore necessary to stagger buildings and orient them in a way that they align with favourable wind direction. This can reduce wind shadow area and the tunnel effect.
As the affordable housing schemes in Telangana have already begun to adopt design features and planning guidelines for improving thermal comfort and liveability of mass housing, CSE said that this can be leveraged further to scale up the applications by making these requirements mandatory and part of the project approval.
CSE recommendations
- Adopt and mandate guidelines and requirements by amending bylaws and Master Plans and creating an oversight system for implementation of appropriate building design, material, layout plan to improve day lighting, ventilation and reducing heat load in buildings.
- Integrate layout/site plan of building clusters to enhance thermal comfort parameters
- Augment and strengthen building bylaws for environmental services and improve access to decentralized services
- Need fiscal strategies to make housing construction and operation more performance based; minimize incremental cost of improving thermal comfort
- Build knowledge, skill and capacity on climate-appropriate design, materials, and associated tools and techniques to enable the transition