Green roofs last longer than conventional roofs, reduce energy costs with natural insulation, and absorb storm water, experts observed

 A green roof is a roof of a building that is partially or completely covered with vegetation and a growing medium, planted over a waterproofing membrane. It may also include additional layers such as a root barrier and drainage and irrigation systems.

Types of green roofs
There are mainly two types of green roofs: intensive and extensive.

Intensive roofs are thicker with a minimum depth of 12.8 cm and can support a wider variety of plants. However, they are heavier and require more maintenance. Intensive green roofs are essentially elevated parks. They can sustain shrubs, trees, walkways and benches with their complex structural support, irrigation, drainage and root protection layers.

Whereas extensive green roofs are shallow, range in depth from 1.5 mm to 3.0 mm and lighter than intensive green roofs. In addition, these roofs require little maintenance as well. They usually exist solely for their environmental benefits and don’t function as accessible rooftop gardens

Bunch of benefits
Green roofs last longer than conventional roofs, reduce energy costs with natural insulation, and absorb storm water, potentially lessening the need for complex and expensive drainage systems. On a wider scale, green roofs improve air quality and help reduce the urban heat island effect, a condition in which city and suburban developments absorb and trap heat. During day time translucent sheets provide natural light which reduces electricity costs.

“Metal Scope being an active member of CII-Indian Green Building Council’s (IGBC), understood that the concept of green roof is gaining major importance in India, considering the tremendous benefits that it offers,” says V Santhanam, Founder Chairman, MetalScope (India) Pvt. Ltd. “The demand for pre-engineered buildings is increasing with increased emphasis on green building construction. The PEB structures are created with a high proportion of recycled content, making them lighter by about 30 per cent than the conventional steel buildings.”

Alok Kumar Senapati, Marketing Manager, Dion Incorporation, says, “A green roof serves several purposes for a building, such as absorbing rainwater, providing insulation, creating a habitat for wildlife, increasing benevolence and decreasing stress of the people around the roof by providing a more aesthetically pleasing landscape, and helping to lower urban air temperatures and mitigate the heat effect.”

The layers of a green roof must, like any roof, accommodate drainage and protect the building from the elements with a waterproof membrane. But they also must create a growing area and potentially provide support, irrigation and root protection barriers while staying as light as possible.

How it works
It is observed that the initial expense of green rooftops often turns away prospective clients. Green roofs require professional design, careful structural analysis and multiple layers and systems.

However, long-term economic benefits outweigh the start-up costs. Green roofs protect the roof membrane from harsh weather and ultraviolet radiation. They can last twice as long traditional roofs and also have a fairly stable surface temperature. The extra growing medium and vegetation insulates the building from intense temperatures and minimises heat gain. It is observed that even a six-inch extensive green roof can reduce summer energy demands by 75 per cent.

These benefits are proving to be encouraging factors to build green rooftops. Green roofs mitigate water runoff and sewer overflows. Vegetation and soil act as a sponge, absorbing and filtering water that would normally plunge down gutters, wash through polluted streets. A green roof’s plants remove air particulates, produce oxygen and provide shade. They use heat energy during evapotranspiration, a natural process that cools the air as water evaporates from plant leaves.

Evapotranspiration and the shading provided by plants help counter the urban heat island effect brought about by an excess of reflective and impermeable surfaces in cities and suburbs. As urban heat islands increase temperatures in urban and suburban areas, they amplify the demand for air conditioning and launch a cycle of energy consumption that contributes to global warming. If green roofs become a common building initiative, cities can reduce the uncomfortable effects of urban heat islands.

Demand drivers
Increase in construction activities and requirement of more aesthetical appeal and durable material are major demand drivers of metal green roofing. In India, increased demand could be attributed to increased infrastructure building activities. Green roofing is available in various profiles and designs. Also colour coated roofing systems are increasingly sought after as it gives pleasing look to the building.

Green roofing offers virtually unlimited design possibilities. Architects can bring their imagination to reality by using various combinations of green roofing and cladding, aluminium panels and value-added glass.

Solutions provided today
Now here it would be useful to have a look at the solutions that are offered today by current players.

“MetalScope Engineering and Design Systems ensure optimum usage of steel in buildings,” assures Mr Santhanam. “Metal Scope pre-engineered buildings can be relocated, making them adaptable for different applications and extending their usable life.”

Informing about the Dion products, Mr Senapati says, “Dion UPVC sheets reduce heating by adding UV and thermal resistance value and reduce energy consumption and sound pollution as well. These sheets can be used in all applications of roofing and cladding i.e. residential, agriculture, industrial and commercial.”

Dion UPVC sheets are available in different range of thickness i.e. 1.5, 2.0, 2.5, 3.0 mm and come in different colours as well including green, blue, white, ivory, terracotta, grey as per the requirement of applications.

Conclusion
Green roofs replace a hard infrastructure with one that’s not only more efficient, but also beautiful and useful. As environmental awareness is increasing worldwide; global warming is becoming major concern. India is also playing a responsible role by using eco-friendly material.

Over a period of time, it is observed that roofing materials and their supporting elements are being considered for lightweight, recyclable, and allowing use of natural light source as much as possible. Therefore we can expect that green roofs will find their place on large scale in future and the green roofing industry is likely to expand in the upcoming years in India. 

A green roof serves several purposes for a building, such as absorbing rainwater, providing insulation, creating a habitat for wildlife, increasing benevolence and decreasing stress of the people…

Alok Kumar Senapati,
Marketing Manager,
Dion Incorporation

The PEB structures are created with a high proportion of recycled content, making them lighter by about 30 per cent than the conventional steel buildings.

V Santhanam,
Founder Chairman,
MetalScope (India) Pvt. Ltd.