Green technologies in Nawabi & colonial architecture of Oudh - September 2016
Are Lucknow's monuments infallible and structurally stable? Despite popular sentiment and hype, the answer would be a resounding “no”. The heritage buildings we see today are but a fraction of what existed originally. Although the British demolished many heritage structures, due to their own political compulsions, it is also true that several buildings were restored by them and these remained under continuous renovation and restoration from 1858 to 1947.
Kothi Dilkusha and Kothi Roshan-ud-Daula were declared unsafe by them; Dilkusha was partly demolished and Roshan-ud-Daula Kothi was shorn of its upper-most floor and signature elements, which were apparently adding unnecessary weight to the main structure. Bibiapur and Musabagh Kothi were abandoned. Moti Mahal vanished. Post Independence, Kothi Darshan Bilas and Gulistan-e-Iram were in use by the UP State Govt, but fell into disuse, due to safety issues. Recently, a portico of the Bada Chhattar Manzil collapsed. Other prominent monuments which were damaged under the vagaries of nature, include the Moti Mahal gateway (during 1923 floods), the Chhota (khurd) Chhattar Manzil (apparently due to subsidence), a side wing of the Hussainabad gateway, a portion of the tomb of Janab-e-Alia (Golaganj), and several others. Two prominent bridges, the Iron (Rennie's) Bridge and Bruce's (Monkey) Bridge, both erected by British engineers, suffered severe damage during Lucknow's persistent floods of the Gomti, and had to be demolished. Lucknow's monuments were also 'seismically evaluated' by the Department of Civil Engineering, IIT-Kanpur, over a period of three years. According to the study, damage to Lucknow's monuments was likely in the event of an earthquake of 7 or above on Richter scale. Lucknow region comes in Zone 3 of the Indian Seismic Code-IS 1893.
It was also concluded that although lakhauri bricks appeared to be no different from contemporary bricks, the mortars used in Lucknow monuments were considerably different than mortar mixes used today for brickwork. Recently, the Directorate of Archaeology, UP Govt, has taken up the restoration and conservation of several heritage buildings of Lucknow and one of the major issues faced by them include the rotten condition of the earlier wooden beams and lintels of the buildings and the difficulty in replacing them, either with similar wooden beams or with steel girders.
Environmental Concerns and “Green” Technologies: Despite the observations above, one has to concur that both Nawabi as well as British-era buildings had been constructed on sound environmental principles, with optimum use of natural lighting, ventilation, sound proofing and passive heating / cooling. Unlike many buildings of today, which consume more and more energy to increase the comfort levels of their inhabitants, Lucknow's heritage buildings utilised passive techniques to achieve the same effect. These approaches can be summed as follows:
1. Solar passive heating i.e. direct exposure to the sun
2. Solar passive cooling through: (i) mass effect and night ventilation (ii) ventilation cooling by cross ventilation, wind passages (tower, tunnel), induced ventilation and nocturnal cooling (iii) evaporative cooling and (iv) earth coupling
3. Architectural techniques: (i) domed and vaulted roof (ii) ventilated roof (iii) natural / cross ventilation (iv) high roof and (v) thick walls
4. Microclimatic controls, including greenery, water bodies and landscaping; light colored exteriors
5. Visual comfort in terms of day lighting factor
6. Noise comfort or acoustic properties: damping of sound by thick walls and high roofs.
Buildings with curved roofs reflected more heat through radiation as compared to flat roofs, due to the enlarged curved surface area of the former. Moreover the hot air within the building could gather in the space under the roof, hence creating a significantly comfortable feeling at floor level. An opening at the top provided an exit for the accumulated hot air. High roofs also provided similar effect. Thick walls, multiple doors and windows placed in such a way that each door and window faced another, ensured that the buildings had optimum cross-ventilation and wind effect. Shape and orientation of the buildings ensured that the entire structure would never face the sun at any point of time, and self-shading was present.
With the British gaining control after 1856, and possibly after observing the climatic extremes of Lucknow, they introduced Rajasthani elements like chhajjas, chabutras and jharokas, in Lakhnavi architecture, while retaining the high ceilings, verandahs, domes (smaller) and landscaping. Many Colonial buildings, e.g. Canning College (present day Lucknow University) and Butler Palace had openings on the rooftops resulting in a chimney effect, through which the hot air collected under the ceiling would move out through convection currents, creating a space for the new fresh air in the lower interiors of the buildings. The roof top openings would also facilitate day lighting in buildings. Another feature was the presence of water bodies (wherever possible) in the form of lakes in the vicinity of the buildings, which added to the cooling effect of the complex.
To conclude, we can say that whatever might have been the construction materials used and the architectural styles of Lucknow's buildings prevalent during a period spanning little less than two centuries (before India acquired Independence), the structures themselves were based on sound architectural and environmental principles. These edifices were structurally sound (within the constraints of the building materials available), attuned to the comfort of the inhabitants, and environmentally friendly. Current restoration work of many such buildings by the UP government (as well as of Constantia, by the school administration of LMC) are unearthing newer secrets and features of these buildings, which are not immediately explainable, but are sure to have served some unidentified and critical purpose, in the not-so-recent past. For example, a warren of tunnels have been discovered, criss-crossing old Lucknow - not only joining the Chhattar Manzil seraglio (Farhat Baksh, Chhattar Manzil, Lal Baradari, Darshan Bilas and Gulistan-e-Iram, but also appearing in as far as Daliganj (indicating a possible connectivity to the erstwhile Machhi Bhavan). It appears that the tunnels had been in use by the Nawabi nobility and their khwajsaras for subterranean movements. But, why subterranean? Awadh faced no military threat, and its rulers never picked up arms, after the Battle of Buxar. The impending invasion by the Rohillas and the “Afghan Peril” remained unfulfilled. So the tunnels are unexplained as of now, although they seem to have been subsequently used as drains, by the British, and much later, blocked, when the waters of the Gomti flooded the tunnels.
In August 2015, a Colonial period weir near Baikunth Dham and a structure made of lakhauri bricks, bound with traditional mortar, cased in a wooden frame surfaced near Kudia Ghat during the ongoing river front development work. Such curious features of Lucknow's Nawabi and Colonial heritage make them immensely interesting and mysteriously attractive to the public in general and to architects, archeologists, civil and mechanical engineers, conservationists, historians, writers, journalists and heritage enthusiasts (like the author) in particular.