TRADITIONAL CONSTRUCTION – AN ENERGY EFFICIENT CONSTRUCTION

Dr K M SONI, CHIEF ENGINEER, WZ-I, CPWD, MUMBAI

TRADITIONAL CONCEPT• Site selection and orientation of the building• Floor height• Verandah/balcony• Courtyard and plants/trees• Concept of bungalow• Design of doors/windows• Concept of sunshade/chajjas• Roof slope and water proofing treatment• Wall thickness• Lakes/ponds/wells/water channels• Use of locally available materials• Concept of Dome• Dressing pattern• No Concept of air conditioning

Site selection and orientation of the Building

• Forts, palaces, religious structures and community structures were constructed at places safe from soil stability, floods, foundation stability, low energy requirements, safety considerations etc

• Orientation of buildings and entrance taken special care

• Water bodies were part of important structures

Floor height• For comfortable conditions inside homes• Not less than 3.5m• Energy efficient • Greater insulation• Mostly no artificial cooling or heating

Verandah/balcony• Verandah, jharokhas and balcony were part of

buildings as per requirement • Verendah cut off direct sun and rains• Verendah were useful for comfortable conditions • Corridors• Walls had small openings so that due to Ventury

effect, air on entering small holes in walls produced high velocity of wind (Hawa Mahal).

HAWA MAHAL, JAIPUR (jaipurhub.com)

Corridor of FRI, Dehradun (Source: oktatabyebye.com)

COURTYARDS• Courtyards were part of houses• Used for religious, social functions and

gatherings• They works as entry place for sun hence

helped in healthy environment• Energy efficient as external lighting was not

required

Concept of bungalow• “Bungalow” derived from Bengal• Bengal hut had openings on top just below

roof level on both sides. This led to air circulation from one side to other in both directions as per the direction of the wind. This kept the hut cool. Tiles or thatch on the roof provided the insulation effect

• This local concept was adopted by the British in Bungalow construction

Bengal hut

Doors/windows• Concept of energy efficiency was adopted in the

design of windows also. Window shutters had many small openings. These small apertures provided cooling due to Ventury effect and also stopped one to see through. These windows were wooden windows and had no glass. Even when they were closed, air came in with high velocity while sun was prevented. This provided air cooling without air conditioners. Later the design was changed and louvers were provided in doors and windows for such purposes.

Sunshade/chajja• Sunshade is essential in our climate and therefore was an essential part

of the traditional construction also. The moist conditions of the windows with temperature suitable for growing insects become favourable conditions for the insects and thus windows are damaged. Sunshades prevented rain water and thus helped in preventing damage to windows. They also prevented sun from getting in which was increasing the temperature inside. The sunshades were essential not only for window shutters but also for interiors of the buildings and energy efficiency as this acted as a barrier for the sun to come in through windows. Though sunshades are provided now also, some of the architects prefer buildings without sun shade which make building energy inefficient and prone to damage. Normally, these sunshades were earlier provided with stones so that they do not get damaged or the window was provided in the recessed portion.

Roof slope and water proofing treatment

• In traditional construction roof was provided with the slope required to drain out the water or with a dome. With the concept of flat roof, traditionally slope was provided so as to drain water from the projected slab by providing slope in the roof. Thereafter slope was provided not in the roof material but in the water proofing materials which also acted as insulation materials. For example mud phuska was provided on the roof which was prepared locally with the soil having largely clay, an impervious material, locally available and economic. Since cracks develop in clay, “bhusa” was added in the clay and mixed properly to avoid cracks as it provided reinforcing effect to the clay. Bhusa was also available locally. Slope was therefore provided in the roof with mud phuska, an economic material than RCC or reinforced brick (RB) which also acted as water proofing and insulating material making buildings energy efficient.

Wall thickness• Traditionally wall thickness of outer walls was provided with

more than one and half brick wall. This was highly energy efficient as it provided insulation effect from the sun and cold. Additionally, during rains, it prevented water to ingress through as joints were cut off through brick, additionally required in one and half brick thick wall and thus no moisture was passing inside making rooms moist free which prevented algae/fungi to grow. Thus it helped in the occupational health of the occupants. In the areas where pipes were embedded or taken out, it was very efficient to prevent seepage as whole section was not disturbed.

Lakes/Ponds/Wells/moats/Water channels

• Traditionally, lakes/ponds/wells were part of the development which acted as ground water recharging, as well water source for the public and cattle. These were also the source of providing water to the trees planted near them. These lakes and ponds were thus also helpful in lowering the temperature of the surroundings thus construction near them was energy efficient as it provided cooling effect.

Use of locally available materials

• Locally available materials are always economic and energy efficient as they require minimum energy in transportation and are generally made from low energy required materials. Mostly they were used in traditional construction except in royal palaces

Concept of dome • Dome was an integral part of the

construction of religious structures and even of other buildings. Dome had high roof and was energy efficient as it provided cooling effect. Also, in other buildings, traditionally top floor was having sloped or domed roof which helped in minimizing the temperature inside building due to its insulation effect. This also avoided the cost of water proofing.

Dressing pattern• Traditional dressing helped in low energy

requirements. Generally, people used to wear dresses and shirts/kurtas according to atmospheric requirements and comforts.It required no external source of energy either for cooling or heating.