COVER STORY

TOUCHING THE SKY

Indian cities are witnessing immense demographic expansion due to migration from surrounding villages, leading to urban sprawl, housing demand, rise in cost ofland. Many citizens all over India migrate to the cities for better jobs and education. Industries, trade and commerce activities and number of educational centres in cities attract floating population from all their surrounding villages and districts. This has expanded the cities in all directions and all aspects of development. With an urban sprawl of kilometres, these face the problems of congestion, pollution, everyday commuting to work place, competition, deforestation etc.

Single tenant or single use: A bank building where the peripheral suburbs have developed tall structures for residential use and eluded high rise structures.

It is costlier to make high-rise buildings because of the design factors: the vertical members like the columns have to be much stronger and as it raises the cost and time of transportation and scaffolding. Thus the price of flats becomes higher and in case of 30 floors, the cost of flat would be about 40% more than that on the first floor. Further the maintenance becomes very costly compared to a conventional low height building.

High-rise structures are also called “vertical cities”, having the potential to decongest urban sprawl. Indian cities are witnessing immense demographic expansion due to migration from surrounding villages, leading to urban sprawl, housing demand, rise in cost of land. Housing has developed into an economy generating industry. Given this demand, while high-rise residential structures have become a solution in the metropolitan cities, they remain eluded in tier II cities in India. Low-rise or mid-rise high-density dwelling types have developed in these cities. A study of Pune city’s housing needs, demands, market, and type of structures being built, reveal that
tall buildings of 11 floors are being developed on the city’s urban fringe. Most of the high-rise projects remain as proposals.

An investigation in this case study reveal that high rise structures are not preferred due to user perception of insecurity in case of fire and high cost of the building. The paper aims at studying the availability and use of fly ash in various proportions, which can be used in Indian high-rise residential buildings. The research paper indicates that fly ash concrete can be used to reduce the cost of construction and has the potential to minimize the damage caused due to high temperature.

Tall buildings throughout the world are becoming popular day by day. With the advent of modern day construction technology and computers, the basic aim has been to construct safer buildings keeping in view the overall economics of the project. A high-rise building, apartment tower, office tower, apartment block, or block of flats, is a tall building or structure used as a residential and or office use. In some areas they may be referred to as “Multi Dwelling Unit” or “Vertical cities”. They have the potential to decongest the urban sprawl on the ground level, and increase the urban density, housing higher number of families in lesser space. Benefits include they act as landmarks; create unique skyline and efficient land use.

Although there is no precise definition that is universally accepted, various bodies have tried to define what ‘high-rise’ means- the New Shorter Oxford English Dictionary defines a high rise as a building having many stories.

Designing of high rises

Wind is one of the most important factors that architects and engineers have to consider when designing tall buildings.

While skyscrapers might appear to be highly-strengthened, immovable structures, all tall buildings are in fact designed with a degree of flexibility in mind. This is principally due to the impact that wind forces – known as “wind loads” – have on a building as it becomes taller. Whilst you might be experiencing a pleasant breeze at street-level, the force of the wind generally grows much stronger the higher up you travel.

While the steel and concrete used in a skyscraper’s superstructure is designed to bend and flex to absorb the impact that these wind loads have, the degree to which the structure is able to move can have a significant impact on the comfort of those inside the building.

Challenges

When buildings first began to grow tall in the 1890s and 1900s, height limits were imposed – such as those introduced in Chicago – to prevent their masses from blocking sunlight. In New York City, ordinances were passed that allowed tall buildings to develop on the basis that they were set-back after reaching a certain height. This allowed sunlight to reach street-level whilst breaking-up the facade and reducing the impact that high winds had on these early towers.

By the 1960’s however, larger, box-like skyscrapers began to come to prevalence, bringing with them a whole host of wind load engineering challenges.

The first problem that began to arise was increased wind velocity at street level. This was principally caused by the “street canyon” phenomenon; an effect that sees large buildings redirect wind down their facades – which effectively act like canyon walls – and funnel it along streets at much higher velocities than in low-rise, suburban areas.

The street canyon effect was particularly notable in Manhattan where the heavily formalized grid structure of the city blocks offered little to break up and deflect winds once they began to blow. Additionally, as wind moved around the top of these tall structures, vortices were being created in a process known as vortex shedding.

Majority of the tall buildings in India are constructed in Mumbai with about 25,000 already in existence and many more approved for construction in the days to come.

One thing is for sure and that’s that the 20th century was surely the century for high-rise buildings. And how do you define high-rise buildings? – Simply put they are buildings greater than 75 feet or 7-10 story high buildings. A building is also termed as a high-rise when it’s out of the maximal reach of fire fighters.

Majority of the tall buildings in India are constructed in Mumbai with about 25,000 already in existence and many more approved for construction. Tall buildings are the dominating symbols of the skylines of big cities and are becoming increasingly man-made marvels, what with mans increasing quest of defying gravity and touching the skies! With every passing decade, the height of buildings has been increasing exponentially; technological advances are being incorporated into building constructions and factors such as wind, gravity and earthquake resistance are being given greater importance. Currently the Burj Khalifa is considered the world’s tallest building with a whopping height of 830 meters!

In Kerala, cities like Kochi, Kozhikode, Kollam, Thrissur and Trivandrum are becoming increasingly inundated by high-rises. It could be due to an increasing population attracted there by the possibilities of greater business activities along with the comforts of having more amenities that are available in cities.

High-rise structures are also called ‘vertical cities’ and provide a practical way of decongesting urban sprawl. Currently, Indian cities are undergoing increasing inundation by indigenes from the rural areas in search of jobs, education and better facilities. This puts immense pressure on the demand for housing, leading to spiraling property costs. Educational institutes, health centers, industries and commercial activities all attract people from surrounding habitations and into the cities. This leads to expansion in all aspects of the city; the bad part is that there is increased congestion, pollution, competition as well as deforestation as the city tries to expand horizontally first.

The lack of horizontal space however, leading to a potential breaking point has led builders to the brilliant solution of building vertically. As with all things good, this solution has also been criticized with many lamenting the loss of the old way of life with the introduction of these tall oppressive buildings that lower the quality of the urban dwellers natural social life. There may be a point there as high-rises do come with their own shortcomings; but with the modern realtors, even these shortcomings are finding adequate solutions now. In large cities where properties are expensive, the buildings logically grow upwards. In smaller towns where land is cheaper, it’s more logical to have horizontal growth; and you won’t be finding high-rises there for sure!

So by strategically increasing the number of homes per plot of land, cities can go a long way in withstanding population growth, while leaving some amount of land free for creating recreational parks for its citizens. This makes the city a great place to live in.

Also, when development happens vertically, it minimizes the physical footprint, while accommodating a greater a number of families as when compared to horizontal expansion. In this way tall buildings leave far more space for public spaces, agricultural land as well as virgin forests.

Thus, commercial and residential high-rises leave precious grounds free for greenery which supports life and social vibrancy.

The city of Mumbai, Kolkata and Chennai host most of the high-rise buildings in India.

Below skyscrapers are based on height in the cities and completed by the time of listing.

Palais Royale (Mumbai) – 320 metres

Palais Royale skyscraper at Lower Parel of Mumbai has 120 apartments and a luxury building with cinema house, spa, badminton court and swimming pools. The supertall building is expected to complete in 2020 and will be the tallest super skyscraper of India with 320 metres height.

The 42 (Kolkata) – 260 metres

The 42 residential skyscraper in Kolkata is currently the tallest completed building in India, The 42 topped off in 2019 and located in Chowringhee with 260 metres.

Imperial Tower (Mumbai) – 256 metres

The Imperial Towers of Mumbai are second tallest completed buildings in India and a residential skyscraper complex, designed by architect Hafeez Contractor.

Mumbai is the city with the highest number of skyscrapers in the world and also host second largest number of under construction skyscrapers, List of tallest buildings in Mumbai are Ahuja Tower, One Avighna Park, Lodha Altamount, India Bulls Blu Tower 1 and World Crest.

Nova 1 (Delhi NCR ) – 180 metres

Nova 1 at Noida Sec-94 is currently the tallest buildings in Delhi NCR based on standard height measurement at 180 metres and a completed buildings in 2018. Supertech Supernova Spira is an upcoming tallest under construction buildings in Delhi NCR.

Urbana Towers (Kolkata) – 171 metres

Urbana Towers of Kolkata were tallest residential complex at entire Eastern India when completed, The 46 storey towers are also first green residential area in Kolkata.

Anchorage, House of Hiranandani (Chennai) – 161 metres

House Of Hiranandani Anchorage is currently the tallest skyscrapers of Chennai city, The residential apartment offers view of the Bay of Bengal and one of the tallest building in South India.

Mantri Pinnacle (Bangalore) – 153 metres

Mantri Pinnacle is a residential tower in Bangalore and currently the tallest building in the city with 153 metres (502 ft) and has 46 floors. SNN Clermont 1 is second tallest skyscraper in Bangalore with 135 metres, followed by SNN Clermont 2,3,4 are also some of the various prominent skyscrapers in the city.

Lodha Bellezza Tower (Hyderabad) – 153 metres

Lodha Bellezza residential towers at kukatpally of Hyderabad are exclusive residential apartments by Lodha Group and the Lodha Bellezza Tower 4, 3 and 5 are the tallest buildings of Hyderabad.

Choice Paradise (Kochi) – 137 metres

Choice Paradise residential skyscraper is currently the tallest building in Kochi and also in tallest skyscraper in Kerala, as well as one of the top five tallest building in South India, located at Tripunithura at 137 metres.

GIFT One (Ahmedabad) – 122 metres

GIFT City is India’s first operational smart city developed in the Ahmedabad and Gandhinagar metropolitan region, stand 122 metre based on standard height measurement, Currently, two GIFT towers are the tallest buildings in Ahmedabad and Gandhinagar.