One can keep the summer heat at bay by taking measures such as treating roofs, growing green patches, etc., writes T. LALITH SINGH
Summer is on and the mercury has started to rise. For ourselves, time to pull out umbrellas, caps, sunscreen lotions and cotton clothes. Find all possible ways to beat the heat and stay cool in a sweltering season that has started to unfold.
To ensure a cool and comfortable stay at home during the season, most end up thinking only about fans, air-coolers and air-conditioners. And to make sure that the power outages do not add further trouble, install power back-up, inverter or generator. Is that all one can do?
May be one can look beyond the reliance on fan, coolers and conditioners. Few maintenance steps can help in making life during the summer that much more comfortable.
Start with the roof and the exteriors since these two are the ones that take the maximum heating. Even as the sun beats down with all its harshness, the walls and the roof stand as a shield for you. Roof is the largest source of heat gain, especially in low-rise buildings, notes the Environmental Building Guidelines for Hyderabad Metropolitan Area prepared by The Energy and Resources Institute (TERI) and Terra Viridis. The guidelines prepared on behalf of the Hyderabad Metropolitan Development Authority (HMDA) calls for proper treatment of roof to reduce heat gains during the daytime. Such treatment provides comfort levels and reduces cooling loads inside a building while thermal insulation reduces conductivity for the roof section.
It is also pointed out that a dark-coloured roof absorbs more heat and sunlight that invariably ends up increasing the cooling demand of the building. “A reflective roof absorbs less heat and reflects incident radiation,” the guidelines point out. Ideal exterior surface coatings can help and so does the white plaster.
The TERI and Terra Viridis report states that “by applying roof insulation in a 24-hour fully air-conditioned residential building, an annual energy savings of 14 per cent is achieved”. This clearly underscores the way such coatings can help keep the interiors cool while reducing dependence on coolers and conditioners.
During the day time, roof insulation offers protection for a structure against inflow of heat. Construction practices in the country mainly involve use of reinforced cement concrete (RCC) as roofing element which has high thermal conductivity.
Some of the methods that the guidelines discuss to tackle this include over-deck insulation i.e., providing a thermal barrier over the RCC to check the sun heat from reaching the RCC slab. Other conventional practices being use of foam concrete and mud phuska or higher albedo (a measure of a material’s ability to reflect sunlight) paints and coats which can also significantly reduce the heat island effect.
Windows also play a key role and the environmental building guidelines say that these openings can achieve natural daylight and natural cooling through ventilation. Windows can also be designed to cut down solar heat gains. On other aspects to keep home cool, adding a bit of green patch around could help and if space permits, big trees at right points could serve shading purpose.
Large canopied trees covering larger areas, depending on available space, can be an ideal way to get some coolness.
Also, shade the entrance and windows with right awnings that could cut down the sunlight entry. Small coir mats on windows and longer sized one for the doors with water sprinkled at regular intervals during the afternoon also come handy in doing away with the possibility of heat accumulation inside.
“A reflective roof absorbs less heat and reflects incident radiation,”