One can keep the summer heat at bay by taking steps such as treating roofs, growing green patches
Summer is on and mercury is on the rise. It’s time to pull out umbrellas, caps, sunscreen lotions and cotton clothes. To ensure a cool and comfortable stay at home during the season, most people end up thinking only about fans, air-coolers and air-conditioners. And to make sure that the power outages do not add further trouble, they install power back-up, inverters or generators. But that’s not all.
You 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. The roof is the largest source of heat gain, especially in low-rise buildings, according to 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 gain during the daytime. Such treatment reduces cooling loads inside a building while thermal insulation reduces conductivity for the roof section.
Dark-coloured roof absorbs more heat and sunlight. “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.
Inflow of heat
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 are 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 gain. To keep home cool, adding a green patch around could help and if space permits, big trees at right points could provide shade. 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 heat.
T. LALITH SINGH
During the day roof insulation offers protection against the inflow of heat