Urban Tune-Up : Architectural Packages for Block-Based Rooftop Spaces as Containers of Public Life

Bangladesh University of Engineering & Technology, Department of Architecture, Faculty of Architecture and Planning, Dhaka

Project idea

At first glance, the idea might seem utopian or excessive. But is it really? Bangladesh’s capital Dhaka offers almost no scope for creating public life. The city is lifeless with no spaces for play, interaction, or green areas within its urban core. Middle and lower-income residents find social life nearly invisible. Public spaces and open areas are practically missing at the city floor level in Dhaka’s dense urban fabric.

During Dhaka’s scattered development, many unseen, leftover spaces have emerged, which lack interaction with city life, but hold untapped potential. In this highly saturated city, rooftops represent the largest urban gap. The idea is to create an interconnected network of rooftops, activated by architectural packages that transform these barren rooftops into vibrant, functional areas. This new elevated layer will bring back social interaction, provide community facilities, and reintroduce green spaces into the urban environment. Typically, parks serve as an escape from the city. Here, however, parks will be an embedded part of the city’s urban infrastructure at an elevated dimension.

The project explores multiple plot-based & block-based rooftop scenarios to establish the new rooftop network. It focuses on the future development of Dhaka by combining insights from local practices (Detailed Area Plan 2022, Dhaka) with international urban design guidelines. Adopting the idea could start a structural movement that could be followed by developers and housing corporations to invest in rooftops.

Project description

Bangladesh’s capital Dhaka offers almost no scope for creating public life. The city is almost lifeless with no spaces for play, interaction, or open green areas within its urban core. Middle and lower-income residents find social life nearly invisible. Public spaces and open areas are practically missing at the city floor level in Dhaka’s dense urban fabric. During Dhaka’s scattered development, many unseen, leftover spaces have emerged, which lacks interaction with city life. These spaces hold untapped potential. In this highly saturated city, rooftops represent the largest urban gap. The idea is to create an interconnected network of rooftops, activated by architectural packages that transform these barren rooftops into vibrant, functional areas. This new elevated layer will bring back social interaction, provide community facilities, and reintroduce green spaces into the urban environment. Typically, parks serve as an escape from the city. Here, however, parks will be an embedded part of the city’s urban infrastructure at an elevated dimension.

The site includes Karwan Bazar-Farmgate and its adjacent areas in Dhaka, Bangladesh. It is a densely populated and built-up area, which makes it ideal for testing the proposed concept. The area will face a massive transformation because of the new Metro Stations, putting it at the center of Transit-Oriented Development. Situated between the Farmgate and Karwan-Bazar Metro stations, the site is within the TOD radius and ideal for block development. Block-based development is a viable strategy, as outlined in the government-issued Detailed Area Plan (2022-2035). So, mixed-use redevelopments will take place along the Metro Line, replacing the small 2-4-6 story buildings built over the network of small plots.

Over the last 30 years, Dhaka has lost 66% of its green space, worsening the urban heat island effect. 90% of the city faces the risk of intense heat waves. The total lack of open spaces and resting spots has created a claustrophobic environment, so the only places for social interactions have become indoor spaces like restaurants, which can't provide the mental benefits like parks and public spaces. The proposed rooftop network could address Dhaka’s urban challenges, such as the urban heat island effect and waterlogging while adding social and economic value. This elevated layer proposes a new economic model in the city, morphing unused rooftop spaces into valuable public spaces.

The design strategy consists of three components. These include a connected rooftop layer for both plot and block developments, architectural packages to tune up rooftops, and an elevated walkway that adds a new dimension to car-centric Dhaka. These elements create an integrated urban system.

Combining data from local practices (Detailed Area Plan 2022, Dhaka) with international urban design approaches, the future development of the site is projected. The master plan for block development, derived from unified plots and the surrounding street network, uses parametrically generated block variations to select the most logical block structure. Hence, the potential roof layer is generated to tune up with packages of architecture.

In Dhaka’s dense urban environment, spaces for interaction and greenery are nonexistent, with only brick and concrete buildings and no open spaces. The architectural packages will grow over these fixed, permanent buildings, turning barren rooftops into a network of public spaces. These packages, consisting of primary folly and roof modules, can accept, adapt and transform with the ever-changing urban landscape. The formations are shaped by the specific roof area and have no designated programs, allowing for flexible uses such as play areas, community events, urban farming, food kiosks, etc.

The proposed walkway between two metro stations acts as a linear vehicle for public life. Utilizing the urban gap created by the 20-22 meter high metro piers, it runs through the space effectively. It streamlines pedestrian movement, interacts with new mixed-use block developments, and eases urban rush from the stations. The main road follows a linear logic due to its long-distance nature, whereas the walkway originates from local logic, resulting in a fluid structure that reflects the surrounding organic urban fabric.

The publicly accessible buildings are assigned into three land use patterns: residential, commercial, and mixed-use. These are divided in two phases: existing assessment (plot-based) and future projection (block-based). Urban tune-up is explored in both existing and future scenarios to evaluate how architectural packages will be morphed into different types of rooftops.

Plot-Based Existing Assessment: In existing residential buildings, rooftop usage varies based on the building owners. This creates a contrast between private and public spaces, with some rooftops open to all and others restricted to owners. Similarly, the commercial buildings could offer public rooftops while maintaining private realm, limited to building users.

Block-Based Future Projection: This approach shows a future-centric network of rooftop architecture where architectural packages will be more suited to this unified roofscape. The elevated walkway from MRT station leads to public rooftops. Deeper into neighbourhood, rooftop gradually transition to private spaces for building owners. It makes a dynamic layering of urban spaces, creating both community engagement and individual privacy.

By activating rooftop architecture, Dhaka can become more future-ready. The lower level will remain a typical heavy, permanent buildings, while the upper level will be a temporal layer in constant motion. The follies are timeless and adaptable. So, the rooftops and the skyline can change and evolve according to the community’s needs. The city core will be architecturally elastic enough to absorb new ideas.

Technical information

The architectural packages will grow over these fixed, permanent buildings, turning barren rooftops into a network of public spaces. The primary materials are tensile membranes, cross-laminated timber frames and inflatables (single/ double membranes).

The proposed walkway between two metro stations acts as a linear vehicle for public life. The vertical connections between the road and the walkway help stabilize the structural framework, keeping it balanced.