Sustainable building design through passive measures

Warm Humid climate of Bengal Region the temperature rises up to 45°C. Ensuring the human comfort and less heat gain the public buildings are designed in north south orientation, dividing the building volumes into smaller Blocks, introducing Mashrabiya for the breathable character. Chawk (Traditional Market) Complex is designed like a pavilion around a courtyard inviting natural light and ventilation. Courtyards and rooftops are two popular gathering spaces in old Dhaka that benefits the building and the basement with natural light and ventilation. The green roof creates an elevated ground of open space for people with the passive benefits of rain water retention, thermal insulation, reducing the urban heat island effect and cooling loads.

Efficient construction and operations

One of the driving decisions related to passive measures was to reduce carbon emission related to construction work by limiting the number of new construction and innovative adaptive reuse of the existing buildings. In prison history museum compound, all the gallery, library, exhibition, and performance spaces were designed by repurposing the existing buildings. The design is intended to create more open space for the dense city, not structures. The new buildings in Zone A and B for recreation and economic activities were created replacing dilapidated structures, without taking up from the open space. Then the site materials were reused within the project and rest salvaged by the old Dhaka’s local vibrant material salvaging business.

Landscape & Biodiversity Integration

Due to unplanned urbanization, the water retention and drainage capacity of the surrounding area greatly diminished. Meanwhile the walled prison area kept its flora and fauna intact within its boundary. The zone A, B and C landscape design rigorously protected the existing foliage, added carefully chosen non-invasive plants to create various pocket parks. The design revived waterbodies to integrate them in the public space design. 2 water bodies were revived, and 3 more were created. Porosity of the site was increased with porous pavers replacing concrete plaza.

Land use & Transformation

The walled protected site area within the world’s most densely populated location, needed to address numerous challenges. The recreational facilities, public parks and pocket parks created desired activity space for a healthy urban life. It created spaces for refuge, water retention in Old Dhaka under imminent threat of earthquake, water clogging and fire hazards. Traffic and walkability improvement measures include a thoroughfare road through the site to lessen traffic pressure, relocation of some roadside structure’s road widening, node redesign. The addition of bicycle lane, Non-motorized vehicle, sidewalk along the site’s periphery greatly increased the walkability of the site. 500 basement Parking to eliminate roadside parking.

Participatory Design

For community needs, various levels of meeting with locals, political parties and government officials were done at every phase of design. Local workers, craftsmen and materials were promoted throughout the work to reduce emissions for transportation. To revive local craft, the design of the mosque integrated ‘jali’, a geometric patterned screen made of cast iron, meticulously crafted by the local craftsmen. Traditional approaches as lime-mortar plaster, hand crafted porous pavers block was experimented and implemented. On-site mockups, trial and testing were conducted to bridge the knowledge of the designer, craftsmen and materiality.

Community Impact and Resilience

The vibrant surrounding community needed gathering urban recreation space and revenue generation activities that were incorporated in the design by creating Park, Playground, Food court, Book shops and wellbeing places for all age groups. To fight the fire hazard of its adjacent area this designed place with many open water bodies will help in future. The shaded open pavilion like buildings, existing and designed tree canopies, decks and drinking water stations will serve as an urban oasis for this hundreds years old locality.

Financial Feasibility

The immense land scarcity and housing crisis in the surrounding could have engulfed this site area in a glimpse. The site owner, the Prisons directorate of Bangladesh, needed an economically feasible, revenue generating idea to give up the valuable land for urban design. The zone A recreational building houses convention hall to host programs, retail spaces, bank, office, Cineplex, gymnasium, pool, rooftop restaurant and paid parking as revenue generating activities. Moreover, ticketed walled prison history museum complex is a revenue generating activity to conserve the archaeology underneath and the prison history above ground.

Aesthetic Qualities and Cultural Integration

Instead of the glass-clad aesthetics of the modern urban fabric, the new buildings opted for the red hued heavily insulated facades inspired from the lime-mortar plastered traditional old Dhaka buildings and earth texture of this old land. The Zone A building surrounds a historic prison building creating the scale of the traditional old Dhaka urban alleyways. The zone B building imitates courtyard and rooftop gathering spaces of the traditional old Dhaka neighborhoods. Surrounding vibrant cultures were accommodated such as food stalls, local business and craft shops, roof-top space to host traditional events like kite flying ceremonies etc.