Renovation of ancient structures using modern technology and materials without denting their aesthetics and historical value has always been a challenge. And when the structure is a temple as old as the Srikalahastheeswara Swamy Devasthanam in Srikalahasti town of Tirupati district, there is no room for error.
The temple had been facing leaks at several spots on its roof for a long time, despite the application of concrete over the years. However, the temple management’s latest efforts, which blend age-old practices with modern technology, promise a lasting solution that also keeps the temple’s authentic beauty intact.
A fascinating origin
Srikalahastheeswara Swamy temple is a famous Saivite shrine revered as ‘Dakshina Kashi’ (southern Kashi). People from south, who find it difficult to visit the ancient town of Kashi on the banks of the Ganga river, offer prayers at this shrine. It is said that a visit to this temple is equal to that to the Kashi Vishwanath Mandir.
Mythology has it that the Shiva Linga here was initially worshipped by Sri (spider), Kala (serpent) and Hasti (elephant), hence the name. Moreover, the story of Bhakta Kannappa, a devotee from the Chenchu tribe who offered his eyes to Lord Shiva, is equally popular among the masses.
The ancient shrine was re-built and developed over the centuries by various kings. Rajendra Chola I of the Chola dynasty constructed the main structure in the 11th century. Temple inscriptions also mention the contributions of Rajaditya Chola, Rajaraja Chola and Kulothunga Chola among others to this shrine.
The hundred-pillar mandapam, considered a sight to behold with its ornate carvings, was built by Vijayanagara Emperor Sri Krishna Devaraya in 1516. It was during the same period that the ‘Raja Gopuram’ (the 120 feet tower at the entrance) was built. It collapsed in May 2010 but was rebuilt in its original form on the same spot and consecrated in 2017.
The problem
The temple structure has a massive common roof spread over 64,000 sq.ft., covering the sanctum sanctorum of Sri Swamivaru as well as Ammavaru, besides the other celestial beings (Parivara Devathalu).
An ancient roof of brick and surkhi (burnt clay) mortar is kept aloft by stone slabs. When it rained, water seeped into the temple through pillar joints and gaps in the roof stones. The issue was addressed for the first time in 2009, when a chemical coating was applied to arrest the leakages, but in vain.
In 2014, the whole roof, except the Ammavari temple, was given a chemical coating, but the leaks reappeared after a year or two. A similar process was undertaken in 2018, with the Endowments Commissioner ordering the application of two varieties of chemicals on a trial basis. Accordingly, Major leak points above Sikhara Darshan, the corridor from Vahana Mandapam to Nataraja Swamy Sannidhi and the corridor from Swamivari Sannidhi to Yagasala, were treated during 2018-19; this, too, turned out to be ineffective in a few years.
Singed by the setbacks, the temple management consulted experts to come up with an out-of-the-box solution.
The Study
Indian Institute of Technology Tirupati (IIT-T), located 20 km from the temple, offered to provide a solution. IIT-T director K.N. Satyanarayana visited the temple in October 2021, along with professors C.V.R. Murthy and Arun Menon (both from IIT-Madras), B. Balakrishna and Prasanna Kumar Behera, both assistant professors from IIT-T.
Archaeological Survey of India (ASI) director (Epigraphy) K. Munirathnam Reddy was also roped in for consultations pertaining to maintaining the heritage structure in its original form. He was also instrumental in convincing the sponsor Uttara Devi Charitable Trust headed by B. Venkateswara Rao of VH Group, Pune, to meet the project cost of ₹5 crore.
The team suggested core cutting to understand the strata details of the Surkhi mortar at select points on the roof. The samples taken were sent to a laboratory in IIT-Madras.
The samples showed at least five layers of brick with lime mortar joints. As the thermal behaviour of plain cement concrete (PCC) and lime mortar are fundamentally different, the overlay of concrete over the ancient roofing led to the cracks. This was aggravated by the rusted chicken-wire mesh in the top layer of concrete. Cracks in the PCC layer led to significant rainwater seepage, which was absorbed by the brick layers.
Before the work began, the expert team visited ancient temples in Tamil Nadu, especially those built during the Pallava and Chola eras, to understand the complexity of stone structures, especially the joints, and to replicate the age-old technical practices to ensure authenticity.
For a pilot, the team selected the roof above the shrine of Goddess Gnana Prasunambika Devi. The concrete layer was removed and the depleted brick jelly lime concrete (BJLC), was proposed to be redone using a mixture made out of jaggery, Kadukkai (hirda) extract, Arabic tree gum, lady’s finger, jute and urad dal.
Sufficient gradient was proposed to prevent rainwater stagnation. “Measures were taken to provide PVC pipes every 30 sq.m. of roof area and grating to filter the dry leaves and debris to avoid clogging of the pipes,” says T. Bapi Reddy, Executive Officer of Srikalahastheeswara Swamy Devasthanam.
How it was done
The concrete overlay was removed by hand, without using any power tools, so as to protect the stone slabs underneath. A fresh weathering course BJLC, compatible with historic material of the roof, was applied after the removal of all the loose and damaged bricks and mortar.
“The BJLC was prepared by crushing jaggery and Kadukkai and mixing them in water, and this solution was added to lime and sand,” says ASI Director (Epigraphy) Dr. Muniratnam Reddy, adding that the consistency of the solution depended on the concentration of jaggery and Kadukkai and that it acted as a binding material of sort when added to lime and sand.
The ideal ratio is 4% jaggery and 2.5% Kadukkai to every litre of water. The solution, fermented for fifteen days, was mixed with lime mortar and injected between the damaged brick layers to strengthen them.
What the experts say
The expert panel that inspected the ancient structure made a few significant observations regarding the preservation of stone structures.
A major issue, according to the panel, is the current practice of using of cement mortar on vertical stone walls to arrest leaks. This should be avoided as it could damage the stone over time owing to the incompatible stiffness and strength of cement mortar. The experts suggest lime mortar as a better alternative.
They also observed that many temple managements resort to ad hoc solutions such as sand blasting. Such a step not only damages the beauty of the stone, but also damage any historical inscriptions the stone may have, making them incomprehensible.
Another issue noted by the experts is the drilling of holes on to stone structures for lighting and other fixtures such as air-conditioning ducting, public address system, security cameras and fire-fighting equipment, to which the Srikalahasti temple was no exception. The experts suggested removal of the air-conditioning outdoor units from the terrace and instead have a centralised AC system away from the historical structures.
Project Srikalahasti took fourteen months to complete, and the experts involved in the project say the structure will last for the next 500 years, with its architectural grandeur intact.
Published – April 19, 2025 09:11 am IST