Why were Mumbai’s building lifts not allowed to go up to the terrace so far?

In Mumbai and many other Indian cities, terraces atop buildings are not typically accessible easily. In buildings that have lifts, the elevators only go up to the topmost floor, so people need to climb at least one flight of stairs to access the terrace – a tedious task for the elderly and for people with disabilities. The Brihanmumbai Municipal Corporation is now set to change that by allowing lifts in residential buildings to go all the way up to the terrace.

On November 21, the corporation cleared a proposal allowing builders and housing societies to install lifts up to the terrace of a building so that this space can be easily used as recreational areas in a city starved of open spaces. The change will be reflected in Mumbai City’s Development Plan for 2034, which is currently undergoing revisions.

Civic officials have claimed that this new norm will be applicable to both new and existing buildings, and existing buildings must be certified for structural stability.

The residents of Mumbai have been demanding lift access to terraces for a long time, and several housing society groups have welcomed the new rule with considerable excitement. However, even as details about the new norm are yet to be released, one question has puzzled citizens: why have authorities not allowed elevators to go up to the terrace in Mumbai’s buildings all these years?

A question of height

At the office of the chief engineer in charge of the Development Plan in the municipal corporation, officials are not clear about the reason themselves. In one news report, an official claimed this was because of an “ambiguity in the Development Control Rules”. Another official told this correspondent: “First we were not giving permission, but now we think that the terrace can be used for recreational activities by the disabled and old people.”

Officers in Mumbai’s Public Works Department gave more specific reasons for not allowing lifts up to the terrace. “The corporation gives permission to construct buildings according to their height, and a lift machine room on top of a terrace would increase the building height by several feet,” said an official in the Public Works Department’s lift inspection office who did not wish to be identified.

The height of a building is determined by the Floor Space Index that civic authorities allow in different zones in Mumbai. This refers to the ratio of the building’s total floor area to the size of the plot it is built on, and the higher the Floor Space Index, the taller a building can be. Typically, a building lift requires at least 21 feet of extra space above the main lift shaft, to house the lift’s motor room.

“If the lift is allowed up to the terrace, the motor room would project further higher, and would modify the height limits granted to the building,” said Pankaj Joshi, an architect and director of the Urban Design Research Institute, an urban planning think-tank in Mumbai. “To extend the lift up to the terrace, the builder would also need to create a closed lobby area to prevent water leakage in the lift shaft. This too would add to FSI.”

With its new norm allowing lifts up to the terrace level, the municipal corporation seems to have side-stepped this problem with ease. According to civic officials, lift construction on the terrace will be considered FSI-free, and specific height restrictions will apply only if a building falls within the city’s aviation zone.

Fear of misuse

Architects believe that another reason why Mumbai’s civic authorities have not allowed lifts up to the terrace so far is the fear that citizens will misuse the terrace space. “The corporation is probably worried that the terraces will be exploited to create additional housing units,” said Hussain Indorewala, an architect from the Kamla Raheja Vidyanidhi Institute for Architecture in Mumbai. “Since the corporation is selling FSI, they would not want it to be exploited.”

However, with the new lift construction norms, the municipal corporation of Mumbai has included a clause that prohibits any construction work on the terrace, to ensure that it is only used as a recreational space.