Intensity of Urban heat island (UHI) effect
Around half of the world’s human population lives in urban areas. In the near future it is expected that the global rate of urbanization will increase by 70% of the present world urban population by 2030, as urban agglomerations emerge and population migration from rural to urban/suburban areas continues. Thereby, it is not surprising that the negative impacts related to urbanization is an increasing concern capturing the attention of people worldwide.
An urban heat island (abbreviated as UHI) is where the temperature in a densely populated city is as much as 2 degrees higher than suburban or rural areas. Why? This happens because of the materials used for pavements, roads and roofs, such as concrete, asphalt (tar) and bricks, which are opaque, do not transmit light, but have higher heat capacity and thermal conductivity. UHI is also decrease air quality in the cities, due to pollution generated by industrial and automobile exhaust, higher extent of particulate matter and greater amounts of dust. Extensive research activities being conducted to mitigate risks related to UHI
What is Solar reflective index (SRI)?
The Solar Reflectance Index (SRI) is a measure of the solar reflectance and emissivity of materials that can be used as an indicator of how hot they are likely to become when solar radiation is incident on their surface. The lower the SRI, the hotter a material is likely to become in the sunshine.
SRI is a scale from 0 to 100. Materials that absorb and retain solar radiation (and so become hotter in sunshine) have a lower number, whilst highly reflective materials (which remain cooler in sunshine) have a higher number.
COLORBOND® steel with Thermatech® solar reflectance technology
For more than 40 years, COLORBOND® steel has revolutionised building design, transforming our workspaces along the way. COLORBOND® steel with Thermatech® solar reflectance technology sets new benchmarks, providing architects, builders and developers better choices to meet the challenges of a changing world. With the Indian summer soaring above 50 degree Celsius; roof is your structure’s first line of defence. And the climatic impacts within the building could be controlled with a thermally efficient roofing system.
Thermal reflective roofing materials with suitable SRI values in its paint system, have been a big focus in recent times and is one of the many vital components considered while planning a structure. Addressing the changing requirements of a roofing system that demands greater climatic considerations. Tata BlueScope Steel, leading coated steel manufacturer offers an innovative energy efficient solution; THERMATECH™ Solar Reflectance Technology that is incorporated in COLORBOND® steel. This High strength light weight colour coated steel provides thermal protection, by optimising solar reflectance properties, which is inbuilt in its material due to the paint system
Thermatech® technology helps your roof and your building stay cooler by reflecting more of the sun’s heat. When heat is reflected away from your building, air-conditioning has an easier job keeping your building cool. Using less energy to cool your building can help occupants save money on energy costs as well as potentially reduce emissions from electricity generation. In moderate to hot climates COLORBOND® steel with THERMATECH® Technology can reduce annual energy consumption by up to 20%, compared to ordinary Pre-painted steel (ordinary PPGL) roofing materials of similar colour but with a lower solar reflectance.
Help Structures Lasts Longer
COLORBOND® steel with Thermatech® technology absorbs less heat from the sun, protecting your roof and its supporting structure from extremes in heat. As a result, the stresses placed on your roof and its materials are reduced and your roof lasts longer.
Even Darker Colours Reflect More Heat
It’s widely known that lighter colours are better at reflecting heat. Now with Thermatech® technology, even the darker colours in the COLORBOND® steel range perform better without changing their appearance. So you can choose from a wider range of colours and still enjoy a thermally efficient roof.
Minimising Environmental Impact
With Thermatech® solar reﬂectance technology, we help in creating a future that is comfortable not just for people, but for the environment too. THERMATECH® Technology is an effective way to reduce the energy load of your building. COLORBOND® steel is a GreenPro certified product by IGBC (Indian Green Building Council). This certification requires the product to undergo a rigorous sustainability assessment. Tata BlueScope Steel is committed to design and manufacture sustainable products and solutions, that are lighter, last longer and use fewer natural resources to produce them.
Watch this video to understand more about Thermatech® solar reflectance technology from COLORBOND steel