Reduction of Embodied Energy and Construction Cost of Affordable Houses through Efficient Architectural Design: A Case Study in Indian Scenario

Abstract

Embodied energy and cost of construction of any building depends upon the consumption of resources, more specifically construction materials. In housing clusters, the spaces provided for horizontal and vertical circulation of occupants such as corridors and contribute in the built-up area of individual unit without any increase in the usable/carpet area. Thus, an efficient architectural planning of common circulation spaces plays a major role in lowering the built-up-to-carpet area ratio of individual housing unit in clusters. This may, thus, result in lesser embodied energy and maximum area availability for occupant usage. In the present study, 30 clusters of Indian affordable housing units (IAHUs) of similar typology and different architectural designs are analyzed. The built-up and carpet area of each IAHU are estimated, and the ratio of the built-up to carpet area is calculated. Detailed estimates of construction materials for each IAHU is prepared, and cost of construction and embodied energy is calculated. The calculations of embodied energy and construction cost are done for major construction materials, viz., cement, steel, bricks, sand, and coarse aggregate and compared with different built-up-to-carpet area ratio. The study of IAHUs concludes that a variation of 1.30 to 1.62 in the built-up area-to-carpet area ratio results in variation in construction cost (INR 13,425.00 to 20,138.00 per m2 carpet area) and embodied energy (4-6.5 GJ per m2 carpet area). Analysis suggests that the IAHU with a lower built-up-to-carpet area ratio exhibits reduction in the cost of construction and embodied energy simultaneously. Thus, an efficient architectural design plays a major role in improving the sustainability of IAHUs and built-up-to-carpet area ratio is an important indicator of sustainability.