If you live in a tropical climate, like me, you obviously realize how important it is to rely on energy to save you from the all-pervasive heat. Then again, you must also be familiar with the large figures on the energy bills that make your heart miss a beat, and frantic calculations are done on paper, in the head, or if you are like me – on your Ipad, trying to manage your fiscal deficit.

If we perchance have darker colored roofs – like 90% of the United States, then the peak heat of the sun has been contributing to more than double the energy need and hence, the deficit.

Before you run to paint your roof, wait and hear (read) me out.

These systems have dual functions to perform. Many people resort to metallic roofs to capitalize on the reflective surface; however what they do not know is that the metal does not reflect infra-red back to the sky. Also, reflective surfaces can, and do – accumulate dirt, and that reduces the benefits substantially. People in colder climates do not particularly care for this as heating accounts for 29% of energy consumption while air conditioning notches a measly 6%. Thus to them, a darker roof makes sense.

I did mention a second reason to adopt these systems. To do that, let me explain the ‘Urban heat island’ concept. Most of our urban spaces and structures are surfaces that absorb the heat due to the material, or color. Smog creation due to the same aggravates the situation further. Add to that, the lack of vegetation, and the ‘heat-gain’ of an urban space just multiplies. Sadly, this means a higher drain on energy reserves.

A cool roof system would ensure, ideally, a negligible heat gain, reflection of UV and Infra-red back into the atmosphere, and a reduced and more habitable environment through reduced use of CO2 spewing air conditioners. Various approaches exist to this effect – One can choose one, or a combination of many different methods.

Inherently cool roofs

Inherently reflective vinyl roofs, with high reflectance and emittance measurements, can reflect 70-80% of the sun’s rays and prevent radiation gain by a building. Compare it to the poor 6-26% reflection of the asphalt, the benefit becomes clearer.

Coated roofs

Applying a solar reflective coating to an existing surface is another option. The CRRC (Cool Roofs Rating Council) website has data on many products in the market.

Green roofs

Many countries have experimented with various strategies when it comes to a green roof. Insulation layers, waterproof membranes, drainage, plants, and sometimes, a wind barrier form the components of a Green roof. The benefits of such a strategy are manifold - Improved air quality, excellent insulation, cool environment & a thriving and unique eco-system.

Governments across the globe are involved in promoting Cool roofing systems to reduce their carbon footprint, save energy costs and demand, and to nudge the depleting environmental sustenance to life