We could learn from the past, since human settlements lived well without ceiling fans and air conditioners.
Open the windows – let the air come in. This line is routinely heard, meaning windows let in air. But do we really get that elusive air every time? If it were, there would not have been ceiling fans and air conditioners.
Does that mean windows do not let in air? No, it means the way we are designing the windows may not be effective. There could be something wrong in the way buildings are located or even the town planning could be flawed. If for thousands of years, human settlements lived well without ceiling fans and air conditioners, there must have been some way of living with air.
Designing for natural air is among the very basics of an eco-friendly building, so the more we capture it, the greater the efficiency. Primarily, it means ensuring cross ventilation, displacement ventilation and body-level breeze.
Cross ventilation is a very common term, suggesting air blowing through the inside of a room. Traditionally, it was achieved by windows positioned in the centre of two opposite walls, with the room itself being narrow enough for wind movement. Nowadays, two opposite walls being external is rare, hence need to shift openings to the wall corners. If diagonally placed, even larger rooms will get more indoor air than otherwise. The corner windows create an eddy, a kind of air movement, pulling in possible stale air from all over the room. Even if we get only two side walls as external walls, there can be up to four corner windows. Typically, the openings stop at lintel level, with no way for the air above 7 feet level to go out. As such, even the fan would keep throwing this warmer air down for a while! As a solution, most homes were having a small void on top of the wall to let out this stale air, now rare to see.
The void atop the wall provided displacement ventilation, an essential approach in passive cooling, now out of practice due to maintenance issues. Imagine, the top void becoming a part of the extended window which could be tall, up to the roof bottom. It could facilitate cross ventilation at lower levels and displacement ventilation at the topmost part.
The space between the lower and upper part can be fixed glass to let in light even if the curtain is pulled, with added benefits like saving on time and money by avoiding the lintel beam. Corner tall windows going up to the roof bottom allow eddy currents by bouncing air to side walls and top ceiling; light up the corners which leads to a perception of a larger room while the verticality creates an impression of spacious room.
Will the window design and location alone solve all our needs for air? No, designing for air needs many more deliberations. It’s time to explore.
Why switch on lights even when there is adequate daylight in the room?
Let us go back in time when only animals lived on earth. They took protection within the elements of nature. Not so long back, during the pre-industrial era a few centuries ago, humans created shelters with materials found in nature. Today, we create shelters with materials made by us.
The distinction between using materials found and made is among the major causes for the ecological imbalance in the construction sector. Humans are habit forming, and we see how easily we have been trapped into switching on electric lights even when there is adequate daylight in the room.
We switch on the fan without fail, irrespective of the natural air inside. Even today, millions of people in villages live with low light and few windows without any complaint. Their senses are accustomed to the available light and air. Most of us have got technologically corrupted senses.
The best example can be how air conditioning has conditioned us, within a few years for the majority and few decades for the rest of us. With our offices, cars, homes and most public spaces air conditioned, we have lost our body tolerance to stay out of it. We have forgotten that human bodies are biologically designed to live with the available temperatures and there are many means of living with heat.
The generations that lived until recently managed to have 6 to 7 people of a middle-class family in a less than 2,000 sq. ft house, managing with available space and building materials. Of course, even now thousands of families across India live with the available light, air, space and materials, but the number of people who aspire for more is increasing drastically. Finally, everything boils down to available resources. Once processed, much is wasted and depleted, while resource unprocessed can replenish itself, like light, air, space and materials.
The very idea of making is an action to counter the nature – if she cannot supply it, we humans will make it. Increasingly, we are even rejecting what is found, in favour of what is made.
Making of good architecture does not need all the marketed manufactured materials; most often they take away the possibility of deeper aesthetic beauty of the building, replacing it with a lavish and superficial surface. Of course, we need to make products for a range of life challenges, be it medication or transportation, but not always for construction.
Generations have lived without electricity, even in crowded areas, using ideas like indoor courts, perforated voids, thick walls, high ceilings, bay windows, mukhamantapas and others.
This is not to say we should live without electricity today, but we need to learn to minimise our dependency on it.
The majority of the poor people on this Earth still live with their five senses aligned with the available light, air, water, space and temperature. If the majority can live so, why not the minority of affluent people?