Summer is here. Burning heat and soaring electricity bills. We chill in air conditioned rooms and sweat profusely the minute we are outside. Blame it on climate change. Blame it on deforestation and reduced green cover.
(Picture used for representational purpose only)
Life in metros is even more miserable. Shrinking parks and disappearing tree lined avenues, cities are indeed concrete jungles. Cities record higher temperatures than countryside due to heat island effect, a sum total of all environmental mutilation resulting in heat traps stuck between high rise buildings filled with green house gases.
We need relief from this heat and so we use more air conditioning, more electricity and lo, it is just adding fuel to fire. How many of us can afford to get away to cooler places? Actually we should be asking how many of us can afford the steep summer electricity bills?
Fortunately, in a country where jugaad is a norm, there are many simple ways of combating heat, without air conditioning or electricity – traditional, household tricks we have just forgotten over the years.
Technically, we have moved in the wrong direction in building design and construction, in terms of indoor cooling. The original purpose of buildings which is to provide ‘shelter’ from harsh weather, is somehow lost its meaning in the last two centuries, primarily due to availability of easy technological aids for cooling and heating.
Igloos are built of snow and mud structures built in deserts. Courtyards gave ample shaded opens spaces and wind flow in houses. The concept of a verandah, the semi-open space covering the external walls from direct sunlight, originated in India and found its way into English dictionary, but is dropped from modern constructions in India.
Brick and lime are replaced by concrete and glass in buildings in majority, which is one of primary factors in increasing indoor temperatures. It is just crazy that how ventilators, the tiny holes below the roof to release hot air from indoors to outdoors, are totally erased from buildings, ignoring fundamentals of thermodynamics, especially in tropical climates.
These are a few technical issues which need to be addressed before or during construction. But what can we do to provide relief to inmates during summer. Here are a few tips and tricks to naturally reduce the indoor temperature and bring down the use of air conditioning.
The points to understand is the basic ways of heat flow from higher to lower temperature and thus the air movement. During day time, the heat flows from outdoors through building envelope to indoors and reverses direction after evenings and night.
Traditionally, people sleep on the terraces or outdoors till late night that is till the building cools down and get back indoors to continue sleep. The building envelope consists of the roof, walls and openings and except for north, south; south-west and west are directions in which maximum heat is generated. In fact, you are lucky if you have tall buildings on the west.
Cutting down sunlight
The first effort should be to cut down the direct sunlight on any of these parts of buildings. The topmost floors experience the worst, especially in summers, when sun path goes directly on the roof head. Balconies need to be covered, especially if they are on the west side.
Roof gardens are popular versions to cover roofs. They not only cut down heat, but also provide nice gardens in otherwise concrete urban areas. Grow creepers or plants in pots. Have a sofa and party in the night on the terrace gardens. If one can afford, there could be swimming pools and lawns too on the terrace.
The double roof
If growing plants is cumbersome and too much of a hassle for urban, working people, one can always have a semi-permanent covered roofing – a tarpaulin, bamboo or cane structure or nylon spread. A double roof with air gap is what is required to keep the roof shaded from direct sun. The air gap dissipates the heat from the first roof to the second.
Dealing with hot air
Fix solar panels that serve dual purpose of cutting heat and electricity bills. Have a verandah around the external walls, a layer of grill with greens. Or just make a green wall, grow an ivy or by fixing lightweight pots vertically, even old plastic bottles be used to grow tiny saplings. A small ventilator also can do wonders to room temperatures. A ceiling fan unfortunately spreads the warm air inside the room, a table or standing fan should be preferred. Shade and curtain doors and windows.
The roof curtains
Hang moist cane and Vetiver root curtains to the other edge of the chajja so that they can be watered. The roots not only filter heat but also let out an earthy fragrance. Open them in the evenings for releasing the hot air from inside.
Architects rant on and on about the need for environment friendly designs and weather-oriented construction methods. The reorientation has to ultimately happen if cities have to stop becoming pools of lava every summer and even at other times when temperatures go up beyond normal.
By: Vasanta Sobha
The writer is a Hyderabad-based Architect