The Rule That Is Keeping Indian Cities Stunted

Stand at any busy intersection in Mumbai's Parel district and the contradiction is visible in every direction.

To the east, a row of five-storey chawls built in the 1950s houses families in rooms smaller than a parking bay. To the west, a luxury tower rises forty floors, its apartments priced beyond the reach of anyone who grew up in the neighbourhood. And in between, a demolition crew tears down a four-storey apartment block. What will replace it? Another four-storey block, because that is all the rules allow.

The rule is called the Floor Space Index. It sounds technical but works simply: it caps the total built-up area of a building as a multiple of the plot it sits on. If the index is set at 1.5 and the plot is 1,000 square feet, the building across all its storeys cannot exceed 1,500 square feet. The cap can be arranged low and wide or tall and narrow, but the total remains fixed. In effect, it is a ceiling on how much of a city can actually be built.

Most people experience it without ever hearing the term. It shows up when an apartment block near a new metro station is demolished and replaced by an identically short one, even though land prices have doubled and demand for homes keeps rising. It appears when offices cluster in one part of the city but housing is pushed 15 kilometres away, turning a short commute into a daily ordeal.

In India's largest cities, that ceiling is set extraordinarily low. Mumbai's base residential limit has been 1.33 since 1991, a figure rooted in colonial-era controls that has barely budged in over three decades. Delhi's sits around 1.2 to 2.5. Bengaluru ranges from 1.5 to 2.75.

In Manhattan, by contrast, developers can build 15 times the plot area. In Tokyo's central wards, projects routinely exceed 10 times. Singapore recently approved two waterfront plots at 25 times. The gap represents an order-of-magnitude difference rather than a minor variation.

What Low Ceilings Feel Like

The consequences show up not in planning documents but in daily life.

In Mumbai, the average resident has less living space than an American prison inmate, a comparison so jarring that it bears repeating. Two-thirds of the city's households share a single room. Between 42 and 55 per cent of Mumbai's population lives in slums, not because the city lacks land, but because the rules prevent enough homes from being built on the land that exists. When buildings cannot go up, people are squeezed sideways, into informal settlements that no one planned and no one can easily fix.

In Bengaluru, where building caps are tied to road width and plot size, housing has been pushed 10 to 20 kilometres from the city centre. The result is a commute that has become a defining misery. Bengaluru was ranked the second most congested city on the planet in 2025. The average commuter loses seven full days a year sitting in traffic. Evening rush-hour speeds fall to 13.9 kilometres per hour, barely faster than a bicycle.

Delhi tells the story through geography. The city's master plan for 2041 has been stuck in bureaucratic limbo for years, approved internally in 2023 and still awaiting final notification as of early 2026. The framework that actually governs building dates to 2007. Rather than allowing taller buildings in the core, it effectively concedes to sprawl, releasing tens of thousands of hectares of undeveloped land on the outskirts for new townships.

Building outward like this costs 20 to 30 per cent more in roads, water, and sewerage than building upward within the existing city. New districts are often underserviced for years, stranding families in half-built suburbs while empty government land sits locked in the centre. The India Infrastructure Report 2023 was blunt about the underlying cause: low floor space limits are a main driver of both sprawl and slum growth.

Where the Affordable Homes Went

Walk into any developer's office in Mumbai or Bengaluru and ask why they no longer build affordable homes, and the answer will circle back to land. When a plot can yield only a handful of floors, the cost of land per flat is enormous. A luxury apartment absorbs that cost and still turns a healthy profit. An affordable flat, priced for a young family or a first-generation city migrant, does not.

The developer's choice is rational. Its consequences are devastating. Across India's largest cities, a vital segment of the housing market has disappeared because it is no longer financially viable to build.

Six years ago, four out of every ten new homes launched across India's major cities were priced within reach of middle- and lower-income buyers. By 2024, that figure had fallen to fewer than two in ten. Luxury housing, once a niche, now accounts for more than a quarter of new supply. In the first nine months of 2025, homes priced above ₹1 crore made up nearly two-thirds of all sales. The market remains intact, but it has shifted away from serving those who need housing the most.

India's urban housing shortage now stands at 9.4 million homes, projected to reach 30 million by the end of this decade. The government's flagship housing programme has delivered millions of units and its ambition is real. But it is working against a market structure that rewards building for the wealthy and penalises building for the poor, a structure that floor space caps help entrench because they keep land costs artificially high.

What Other Cities Figured Out

The rest of the world has not solved urbanisation, but it has learned something Indian planners have long resisted: that allowing cities to build tall near transit, jobs, and services is cheaper, greener, and fairer than forcing them to sprawl. The lesson is not theoretical. It is visible in the skylines and the rent receipts of cities that took the opposite approach.

New York's landmark City of Yes reform, passed in December 2024, raised the residential building limit to 18 times the plot area, the most significant zoning change since 1961. It removed mandatory car parking near train stations and added a bonus for permanently affordable homes.

Another significant component was the legalisation of modest density citywide, including the ability to build accessory dwelling units and small apartment buildings in areas previously restricted to single-family housing. This effectively ended large swathes of exclusionary zoning and expanded housing supply options across all boroughs. Housing production in New York City showed early results, with 23 per cent growth in the ten months since the reform, as of December 2025.

Tokyo builds roughly 130,000 new homes every year, more than four times New York's output, and rents have risen only modestly over 15 years because national-level rules prevent local opposition from blocking projects.

Shirish Patel, the co-creator of the Navi Mumbai plan, offered a memorable comparison before his death in late 2024: Mumbai allows 1.33 times the plot and Manhattan allows 15, but the average Mumbai flat is 250 square feet shared by five people, while the average Manhattan apartment is 1,000 square feet shared by two. For the same level of crowding, he argued, New York's limit would need to be divided by nine.

India's own Economic Survey 2025–26, released in January, acknowledged the gap directly, stating that rules capping how much can be built on a plot push cities outward, raise land values, and create artificial scarcity. The intellectual consensus has arrived. Construction has not.

Signs of Movement

Reform is emerging, cautiously, unevenly, and often through workarounds. In Bengaluru, after the state governor blocked a bill to allow developers to buy additional building rights, the state government bypassed the legislature entirely. An executive order in February 2025 inserted the new rules directly into the city's building regulations, a significant step that revealed how difficult normal channels have become.

Uttar Pradesh went further. In September 2025, it scrapped all height restrictions in Noida and along the Yamuna Expressway, effectively doubling permissible floors from around 23 to 44 storeys. Chennai's planning authority proposed allowing buildings up to 6.5 times the plot area within 500 metres of metro stations, potentially the highest such figure in India.

Two cities offer proof that alternatives work. Hyderabad has never imposed a floor space cap, regulating building size through setback and road-width rules instead. Its housing market is among the most competitive in the country, with costs meaningfully lower than in Mumbai or Bengaluru.

Ahmedabad pioneered a land-pooling model, assembling privately held plots, setting aside land for roads and parks, and returning serviced, buildable plots to original owners. The World Bank has called it a model of planned metropolitan growth. In one district, the city spent ₹166 crore on infrastructure but recouped ₹1,300 crore from increased land values. Neither model has spread nationally.

India's metro network now stretches over a thousand kilometres across more than 20 cities, the third longest in the world. Delhi Metro alone carries nearly five million riders on an average day. Bengaluru's metro crossed a million daily riders in August 2025. The case for building homes and offices near these stations is overwhelming: taller buildings around transit hubs leverage existing roads, pipes, and rail systems more efficiently, reducing the cost of serving each additional resident.

Yet the country has essentially one large-scale housing project next to a metro station actually under construction: the Karkardooma development in east Delhi, which took a full decade from approval to near-completion. Higher building limits near stations exist on paper in several cities. Making them real requires navigating a dozen or more separate government approvals.

Growing Up Not Out

None of this requires dramatic overhauls or futuristic visions.

Mumbai does not need to keep squeezing families into ageing buildings or pushing them further out. With taller construction around metro lines, it can slowly replace overcrowding with safer homes and better services. Bengaluru does not need to keep stretching into longer commutes and gridlock. Allowing more homes closer to offices and train stations can make daily life shorter and simpler.

Delhi, instead of growing endlessly into its edges, can make better use of the city it already has.

It means allowing taller buildings where roads, pipes, and rail lines already exist. It means paying for upgrades as neighbourhoods grow denser, and protecting parks and open spaces where they matter most. The floor space rule itself is not the villain. It is a neutral planning tool used in cities worldwide. The problem is how rigidly, and how low, it has been set in India.

What makes this moment different is the convergence of pressures. The affordable housing collapse makes the cost of inaction visible to voters. Metro networks are expanding faster than the building rules around them, creating vast transport assets hemmed in by regulations designed for a different era. The global comparison, once confined to academic papers, now appears in the government's own flagship economic document.

The Floor Space Index was never meant to freeze a city in place. It was designed to manage growth. Somewhere along the way, in India's biggest cities, it became a tool for preventing it. The evidence for change has arrived. The question, as it has been for decades, is whether governance can finally keep pace.

Note: With inputs from Raghavan S Rao.