CHENNAI: City architects are flooded with queries this season with heat waves putting normal life out of gear. What we feel as heat indoors is contributed by the re-radiation of heat absorbed by various building materials such as concrete, brick, wood etc, that form our roof or terrace. Now, architects are suggesting different ‘smart’ techniques that will help ‘heat-proof your house’.
C N Raghavendran, partner in C R Narayana Rao Architects and chairman of Indian Green Buildings Council (IGBC), said a smart play of thermal mass index material is essential for design of a cooler home in hot and humid climate and is the most challenging where night temperatures remain elevated. It’s used primarily as a temporary heat sink.
If you are a nature lover or looking for an eco-friendly hobby where you can also earn, roof garden or urban garden fits the bill. All you need is a structurally strong terrace or roof. Now spread a layer of water-proof membrane, water drain perforator, geo-textile membrane and 6-inch soil for growing vegetation, in sequence. Urban farming by planting tomato, chilly, greens, etc will also reduce your vegetable bills.
Sekar James, MD, Master Plan Landscape Architects, said there had been a huge demand from the Chennaites to suggest ways to regulate heat inside their residences. Terrace garden is an excellent method among several others.
Another quick fix solution to heat-gain is by painting the entire terrace area with heat reflective paint. The higher the Solar Reflective Index (SRI) value, the higher your terrace reflects heat away. It has the ability to reflect or resist heat on all roof surfaces such as RCC, concrete, metallic, asbestos, GI, galvalum sheets, pre-coated roof sheets and poly-flex.
You can also use Thermatek weather-proof SRI tiles that’s hygienic, easy to clean, moisture resistant, stain proof, fire proof, fade resistant, long lasting and easy to lay. It is cost efficient and environment friendly too. Moreover, this tile is available in various colours.
A C Ravi Rangaswami, CEO, ALA Inc, said Thermatek tiles are manufactured using indigenous patented ceramic technology which makes them 25% more efficient than any other cool roof technology available globally. “The tiles reduce the surface temperature by up to 20-degree celsius. To understand this, take a barefoot walk at noon in blistering heat, but still you won’t feel the heat because the SRI value of the ceramic titles is 104, the best in class,” Rangaswami said.
Traditional age-old practice is to water the terrace hoping that it will cool the roof. However, water will evaporate soon. Alternately, line your terrace area with series of inverted earthen pots.
Spray water over the pots every morning at 11 am and every evening at 4 pm. You will definitely feel the drop in temperature indoors. The air trapped inside the inverted pots is cooled by the sprayed water and acts as insulation to your terrace.
In traditional homes, the age-old practice is to provide brick jelly and lime concrete terracing above the RCC roof slab or Madras terrace roofing, as the case may be. This course is laid to a slope so that rain water flows along the designated slopes to rain water outlets.
Do-it-Yourself Kit
The State government has enacted ‘Do-it-Yourself’ kit under Urban Horticulture Development Scheme, to enable city dwellers to grow vegetables in the available space on open terraces in residential flats and individual houses
“With the advent of energy in Conservation Code and also the Green Building Design principles by Indian Green Building Council, better comfort levels are achieved if the thermal insulation of roof is enhanced more than what the traditional brick jelly lime concrete provide,” said Raghavendran.