Feb 26, 20205 min read

Eco-Friendly Redevelopment of the Pegasus Campus in Bangalore

Updated: May 16, 2020

Pegasus Institute, Bangalore Campus by Manasaram Architects

Located in Vasanthanahalli and spread across 8.72 acres, the Pegasus campus is being redeveloped into a sustainable hub integrating the concept of connecting all build-able spaces with nature.

The intent of project was to develop Pegasus institute, Bangalore campus in sustainable way. Pegasus Institute for Excellence works with organization, institutions, and teams to discover talent, build ability and realize their potential through soft skill development. Their campus is located near Vasanthanahalli and is spread across 8.72 acres. All building and development over the past 20 years at the training center was done with local mason guided by ex-military people with plastic, steel etc. for most of the structures. These building have deteriorated over time due to negligence of proper construction materials and technique during construction. Hence to develop the entire campus in an eco-friendly way, the client had contacted Manasaram Architects.

Design Philosophy:

The concept was to connect all build-able space with nature. These spaces would be an extended area of the nature under a roof. The materials which can make this possible would be natural materials like bamboo, local wood, mud and stone which would be locally available and low on embodied energy. Each of the spaces was designed with no wall and huge roof projections to prevent the direct heat gain. Additional screening is provided with bamboo blinds which runs along the edges of the roof till plinth and is rolled up when required. The spaces are lit with natural light and clerestory in each hall that allows the hot air to escape out. In the first phase, the amphitheater, rectangular hall, circular hall, rainwater harvesting tank along with percolation well for water recharge were taken up. Sewage treatment also has been provided.

Amphitheatre:

The existing amphitheater was in a triangular piece of land adjacent to the main circulation pathway. The idea was to work with the existing stage and seating and thereby reduce the material, effort and cost that would go into demolition. Having said that, the seating had to be revamped as per anthropometry and finished with a suitable flooring. A roof was proposed over the stage and the seating to shield it from the elements and to harvest the rainwater. The roof over the seating area had to incorporate the existing trees and had to blend with surroundings.

Conceptual sketch of the proposed new amphitheater

The roof over the stage is a hyperbolic parabola curve and is oriented so that the existing trees are not disturbed. The main frame of the roof is made from bunching a number of bamboo splits together. 2” dia bamboos were bent and fixed over the frame to form the ribs along one direction. Further a grid of 1” bamboo splits was placed at 6” center to center along both axis to achieve the profile of the curve. The bamboo roof is covered with tarpaulin fabric with a coating of brush bond on top for waterproofing.

The seating area had existing steel columns. The height of these columns was low and obstructing the view from the last row. Hence 3” dia bamboo was fixed to the existing steel column to get the desired height. The roof has two numbers of 2” dia bamboos as beam along both directions resting on these columns. Further rafters in 2” dia bamboo are also placed to reduce the grid further down. Bamboo splits are used as infill between rafters and is covered with the same fabric with brush bond on the top.

View through the seating area showing oxide flooring

In the seating area, the height of the existing brick wall was altered and finished with yellow oxide flooring. A ramp along with wider seating area for the wheelchair was added to make it universally accessible.

Hall complex:

This area is at the heart of the 8 acres site. There were 2 existing hall, one circular and rectangular. The proposed complex also consists of these halls respecting their location and is connected by a 90feet long covered pathway. The covered pathway opens a to lotus pond on one side with vegetation on the other. The rainwater of both halls and the pathway is connected to underground tank of 1lakh litre capacity and the overflow goes to the lotus pond.

3D view of the pathway connecting rectangular and circular hall with the lotus pond

Rectangular hall:

The existing rectangular hall was around 1700sqft and had metal truss and thatch roof. This structure had to be demolished and a new rectangular hall had to be built at the same location using local and low energy materials. The buildings are primarily made from bamboo and bricks. The hall is a simple rectangle measuring 63’ by 27’ with a stage on the shorter side and opening on the other side. The structural system of the rectangular hall is bamboo truss made out of 3” dia bamboos placed around 9feet apart. This truss is at two levels forming the clerestory for the hot air to escape out. All trusses are connected with various beams at different level. Above the truss 2” bamboo rafters run at every 2feet and hold the grid of bamboo split above. The bamboo splits are 25mm wide and 10mm thick and are placed at an angle 6”c/c on both directions. This grid distributes the load of the roof above.

The roofing material used is beaten bamboo, an alternate to conventional roofing material which is more eco-friendly. In beaten bamboo, the round bamboo is flattened out and the node is cleaned. 'Dendrocalamus Giganteus' was used in this project for beaten bamboo. The roof composes of two layers of beaten bamboo with tar sheet in between for waterproofing. These layers are held in position with the help of bamboo splits at regular intervals. Solar panels cover the southern side of the roof and would make both halls self-sufficient on energy.

View of the roof with bamboo mat from outside

Circular hall:

The existing circular hall was around 40feet in diameter with a steel column in the center. Because of a steel column in the center the effective usage of the hall was reduced. The new circular hall was proposed without the central column. 40 feet diameter was also increased along the perimeter as the circular hall turned into a spiral on the ground. The structural system is similar to the rectangular hall with 12 numbers of bamboo trusses from 3”dia bamboos. The roof spirals around as it reaches the centre and forms 3 roofs at different levels with gap in-between them for hot air to escape out. The roof at the lower level spans out and forms the roof for the pathway and continuous till the rectangular hall. Both the circular hall and the pathway are currently under construction.