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Architects: CollectiveProject
- Year: 2021
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Photographs:Ben Hosking
Text description provided by the architects. The Debris Block House is a private residence in Bangalore, India, close to the city's center. Debris material from the existing building on the site was used to create mud-concrete blocks for the new home. The ground floor was cast in exposed concrete with an open floor plan, and on the upper levels, the blocks used for the wall construction were left exposed. At the center, a sculptural staircase is washed with light from above with strategically placed skylights at multiple levels. Large planters at every level obscure the building from passers-by as the building blends into the surrounding foliage.
Client Brief, Planning Constraints, Materials + Methods of Construction - Located in a quiet but dense residential neighborhood on an inside corner, the site posed a unique challenge in layout planning and construction staging. With limited road frontage, our goal was to have the home disappear completely with planting in contrast to the neighbors' heavily plastered and painted facades. The program requirements meant that the 3,000 sqft plot was built to allow for setbacks, except on one side, where the footprint pulled back to respond to a large mango tree. Large planters were integrated at every level to compensate for the limited garden area.
The internal planning of the four-bedroom house was driven by the specificities of the family's lifestyle, with a central atrium and sculptural staircase that provides visual and physical connections across all floors of the home. For the couple and their young daughters, proximity between rooms was essential to the brief, with their bedrooms opening onto a tv room and library on the first floor. The atrium is the widest on the second floor, with a bridge connecting a small music room and a personal office. The open terrace with an exposed concrete pergola provides a space for outdoor dining with additional shade from the mango tree branching above. On the ground floor, the living, dining, and kitchen flow out to the landscape beyond with large sliding glass panels that open completely. A small bedroom is located off the entrance, allowing for flexibility and providing privacy for guests.
Extensive research went into developing the mud-concrete blocks created using the waste material from the existing 50-year-old house. The debris from the demolition was broken by hand, remixed, and cast in custom molds to create the final sundried blocks. On the upper levels, the blocks are complemented with porous jali screens that allow for natural ventilation and security at night.
Innovation - Few cities in India have seen as much concurrent growth and rampant destruction as Bangalore. Famous for its dense tree cover, mild climate, and abundant lakes, the city benefited enormously from the country’s economic liberalization and engagement with the world economy. Rapid urbanization and unregulated sprawl came at the expense of natural resources, including the encroachment, filling, and un-regulated dumping of construction debris (from the demolition of old houses and under-performing commercial buildings) into the city’s lakes and waterways.
To address this problem, we questioned if building demolition debris could be considered a resource, instead of generating waste, to create new components for construction. Our interest was in an accessible, minimal energy impact, and cost-effective solution that could be executed by semi-skilled labor on-site using manual molds and locally sourced admixtures. In 2018, our research began under the advisement of a retired scientist from the Indian Institute of Science who directs a local organization promoting earth construction. He advised us on possible mixtures using lime, soil, cement, and demolition debris, which we documented and cast into blocks and tiles to study color, finish, and durability. Our final samples were then lab-tested to ensure their structural strength, which surpassed that of the typical concrete blocks commonly used in local construction. We continue to explore ways to optimize cost, time, and material, not only as a responsible solution to the city’s growing problem but as a way to capture the history of a site while transforming it into something new.
This home and supporting research provide a roadmap for responsible construction. Over the past few years, we have been approached by architects across the country who are interested in using a similar process. Construction waste is a resource, and it can be used in a way that still celebrates design and space-making.
