Steel is Green too
The Hindu, November 2012

With long-term, value accruing to builders through its flexibility, adaptability and lasting appeal, steel is also a cost-effective solution, says Ashok Ranka, in an interview with RANJANI GOVIND.


The Sunshine Towers commercial complex in Mumbai is made of structural steel and is 180 metres high (591 ft.) with 40 floors.


The green building movement is gaining momentum across the world, and what could add more support and strength to the cause than steel itself, queries Ashok Ranka, Director, Ranka Steels.


He was speaking to Property Plus on the increased use of steel in the construction industry’ today. “It’s a healthy trend,” says Mr. Ranka, closely observing the importance thrust on steel in buildings over the last two decades.


“The real estate industry is slowly but surely waking up to sustainable aspects that steel brings to a building, and we are witness to an increasing use of steel for construction purposes,” he says.

Understanding the characteristics of materials that go into a building and why some of them are termed green is essential here. The term ‘green’ used for ‘steel’ is in itself something new.
But is it just because it is an alternative to wood, thereby helping retain the green cover, or does steel possess other characteristics that label it green is something that Mr. Ranka demystifies in this interview.

What does steel mean in construction?

Steel is one of the most sustainable structural materials promising many social, environmental and economic benefits such as low waste, reusability' and recyclability. It also offers flexibility for offsite manufacture, speed, resource efficiency, adaptability and demountability.

But how is steel termed sustainable?

Steel is a fast and safe construction material. As it can be manufactured at a factory and assembled on site, the reduced time on site means lower costs, quicker returns and less disruption to the local community. Besides, there is no waste at the site, and even the waste generated in the manufacturing process can be easily returned to the steel supply chain.

What are the material advantages both for builders and users?

Steel offers builders the advantage of high strength-to-weight ratio. This resource-efficient material results in reduced emissions due to fewer deliveries. What makes steel a green material is also the fact that it matures with age, instead of deteriorating and decaying like some other materials do. To be sustainable, any solution has to be economically viable. And this is where the use of steel offers better returns to users/builders, as it is not only fast, but efficient and predictable too. Production of steel involves a highly automated process and is not labour intensive. With long-term value accruing to builders through its flexibility, adaptability and lasting appeal, steel is also a cost-effective solution.

You also say steel is multi-usable and multi-cyclable...

The reusable and recyclable benefits of steel make it a highly sustainable material in the construction industry. Builders can either take down whole buildings made of steel and rebuild them elsewhere, or reuse individual elements according to their requirement. An increasing number of buildings are now being designed keeping this aspect in mind.


Besides, any steel which is not reused is recycled for further use in construction or other industries. While most other construction materials can also be recycled, the difference in recycling steel is that it can be recycled indefinitely without loss of property or performance. This is referred to as multi-cycling. On the other hand, most other materials are recycled once to a lesser use, which is called down-cycling.


As it enables multi-cycling, steel always has a value guaranteeing that virtually nothing is ever disposed off to a landfill. All steel is recyclable and will be multi-cycled many times without any artificial stimulus.

So steel has social benefits too?

Industry analysts say that over 500 million tonnes of steel is mutli-cycled worldwide each year. According to research data, about 99 per cent of structural steel arising from demolition sites in the U.K. is recycled or reused. Conservative estimates peg the recycling of all steel scrap available each year at over 80 per cent. Many large-scale modern steelmaking processes produce steel with a significant recycled content, since scrap steel is a standard input.

What are the other factors that steel can contribute towards encouraging sustainable development?

To help make zero-carbon buildings a reality, Tata Steel Europe (formerly Corns Group) and British Constructional Steelwork Association have embarked on a new initiative — the 'Target Zero' project. This project will provide the construction industry guidance to meet emission reduction targets, helping it move towards a zero carbon level by 2019. Target Zero will look at five major building types — school, warehouse, office, supermarket and mixed- use development — and generate fully-costed solutions for achieving the targets.


Experts say the carbon dioxide emitted during production of one tonne of structural steel is 0.76 tonnes. Though this is higher than some other construction materials on a tonnage basis, one tonne of steel goes a great deal further than other materials, thus lowering the actual carbon footprint of the structure.