Building Material Services Bank: A catalyst for rehabilitation and reconstruction
An effective approach for the design of Reconstruction and Rehabilitation packages would be to understand the need for building materials, buildings and livelihoods and catalyze the conversion of this need into demand for sustainable building materials and Sustainable Building Technology Enterprises. One of the critical components of the delivery process in any rehabilitation and reconstruction (R&R) Program include the building material and services banks, supported by the mobile building centres and the village construction teams.


Building materials and service bank, Astrang - Orissa The building materials and service banks (BMSB’s) are the critical anchors of the building technology and housing delivery of any R&R program. Located at the "field implementing centres" these banks are designed to provide basic building materials like cement, aggregates and steel for the program, by procuring materials in bulk to ensure economy and quality. These banks further provide services related to the organisation of the village masons into construction teams, training the local artisans and ensuring the shelter.

The BMSB’s should be realised at the project conceptualisation stage and, should be so designed that they continue to function and serve the community beyond the project requirements and form important delivery nodes of improved shelter to the community in and around that region. These community managed BMSB’s are envisioned to be economically viable in their functioning and financially profitable enterprises in the long run.


Development Alternatives experience in R&R activities initiated after the UttarKashi earthquake in 1993 and followed with the Latur and Jabalpur earthquakes have built in capacities and strength with the DA group to provide holistic response packages.Building Material and service bank, Astrang - Orissa

The latest example would be an ongoing program in the cyclone-hits regions of Orissa. As a part of the customized response package for these regions, BMSB’s have been set in two districts of Orissa with the sole aim of rehabilitation and construction of Cyclone resistant Core Housing, Technology transfer and capacity building of local partners and village community. The two Building Material and Services Banks are located in Astrang, District Puri and Balikuda, District Jagatsinghpur, these being the nodal centers of the program.

The functions of these Building Material and Services Banks, like any other, are the production of building materials for the core houses and the construction of these Core Houses using the services of local village masons. Training of various production and construction related trades are also a part of the BMSB’s core activities.

The important functions of the BMSB’s can be listed as follows:

  • Production of building elements.
  • Training in production of the building elements to building material producer artisans and the supervisors’ in-charge for ensuring transfer of technology.
  • Training to masons, bar-binders, welders, carpenters and other affiliated trades.
  • Demonstration of building technologies - equipment, products, production process and applications through demonstration construction.
  • Provision of building elements on demand to the community accessing the Bank.
  • To provide guidance and technical advice to the community accessing the Bank for house planning, technology choice, designs and construction.
  • To keep a record of skilled masons and artisans trained in construction and building material production and network with them as and when the need arises.
  • To provide expert construction services through its teams of trained artisans.
  • To organise credit for housing through link up/networking with financing institutions.

Our experiences on the fields have shown that BMSB’s are the most effective sustainable delivery mechanisms for improving local habitat. They add on to the local economy helping in rural development, as they are Community managed systems. Go to top...



Wrath of Vasuki…How do we cope?

 Earthquakes are sudden geologic movements - tremors that create shaking at the surface. Earthquakes have been objects of great superstitions and awe throughout recorded history. The severe quakes wreak catastrophic havoc in the human community because of destruction of structures - houses and buildings, bridges, roads, railways and uprooting of transmission towers. Death comes in a violent form - at times to hundreds and thousands.


Earthquakes occur in all continents - in Mediterranean Europe, North Africa, Central Asia, Indian sub-continent, East Asia, the Americas and even part of Australia. Everything happens suddenly-without warning. The first distressing factor is collapse of dwelling units. Although measuring instruments at the Seismological Laboratories are able to measure the geologic disturbances, nothing has been invented that can forecast an "earthquake" as we understand it. Human knowledge has yet to cross this frontier. But death and destruction can be prevented or vastly minimised if the houses are structurally sound. In a poor country such as India, which is struck by severe earthquakes every now and then - the last two major destructive ones bring in Uttarkashi region of Uttar Pradesh and Latur district of Maharashtra-the problem of appropriate ‘safe’ housing must receive adequate attention from architects, engineer, builders, and owners of property.

Presently India is tentatively divided into six seismic zones. Each place finds itself in one of these six zones, which represent increasing probabilities of earthquakes of hazardous magnitudes. This division, however, does not rule out possibilities of major earthquakes in "safe zones" also - for example Latur was in ‘low risk’ region when it hit the headlines. In such cases only the map is modified, thus bringing Latur from Zone 2 to Zone 5. Earthquakes being so unpredictable and so dangerous necessitate precautions even in so called "safe" zones.

There are no earthquake-proof houses

Another misconception commonly shared is the at some houses could be made earthquake proof. The reality however is that by taking up precautions, the earthquake resistance of the house is increased finitely, to make them resist quakes of specific magnitudes. These houses, too, may fail once they face quakes having more intensity than their design took care of. A recent earthquake in Japan could cause so much destruction in an otherwise ‘prepared’ Japan because the quake had a vast component of unprecedented magnitude thus making most structures vulnerable.

The movement within the earth’s crust manifests itself in the form of waves that reach earth’s surface and cause vibrations in structures. The structures fail and collapse under the action of these vibrations. These vibrations may be in horizontal direction, in vertical direction or combination of both, which generally is the case. The vertical component of seismic force creates repeated changes in the weight of structures while the horizontal component induces. These forces get commanded in each cycle.

Houses collapse as a result of these inertial forces. Under the action of earthquake the lower portions of the structures which are in direct contact with the ground tend to vibrate more; whereas due to inertia the upper portions of the structures tend to remain static. The resultant stresses build up fast with the increased frequency of vibrations leading to failure of the structures.

The Lature disaster came about when huge stone masonry walls gave way under the earthquake bringing down with them the roofs that were overlaid with thick clay. The walls and roofs were heavy; the masonry was badly made with round stones. The houses were not ‘engineered’ units, but more an assemblage of materials. The mud mortar used was weak and could not provide enough cohesion to sustain the walls on that fateful night. The huge mass of construction material led to a massive disaster.

The magnitude of the inertial forces increase as directly as the weight of the houses. The heavier the house, heavier is the destructive force. One important consideration in making a house more earthquake resistant is to reduce its mass and making it as light as possible.

Traditional poor man’s houses in the tropics have mostly wattle and daub walls with thatched roofs - these houses consume little material, and are light by weight. The inherent limitations of the houses do not permit higher storeys. Additional advantage these houses afford is that due to their lightness, the houses, even if they collapse, may not kill people.

Another way of improving earthquake resistance is by way of making the houses rigid, viz, making sure that the houses vibrate together as one unit. This prevents unnecessary absorption of energy by the structural members and improves the quake resistance of buildings. Schematically, in such houses the top portions of the houses are so joined to the bottom that all movements are transferred immediately from lower levels to the entire building and the entire house vibrates as one rigid body. Consequently no disharmonious stresses are set up and the house remains safe.

The bamboo construction in North-East India follows this principle of Rigid house. Bamboo being light gives added natural advantage. In these houses rigidity is achieved by means of cross bracing and triangulation. All joints are strengthened by means of cross members that can transmit earthquake forces directly to the remaining portions of the house.

Reinforced concrete ‘frames’ are rigid by design and their rigidity can be improved further by small increases in steel used. The ‘framework’ of such beams and columns can be made to resist earthquake-induced vibrations of considerable magnitudes. Almost all the multi-storeyed buildings in towns and cities are framed, thus the structure finds great support. It must be noted here that though the RCC frames take care of major portions of earthquake induced forces, the forces generated in the non-load bearing walls could still lead to damages byway of wall collapses. In places like rural India where concrete technology has little reach, masonry in brick and / or in stone takes major share in the form of lead bearing walls


The strength of masonry depends to a great extent on the strength of the mortar joining them to distribute the earthquake-induced forces equally throughout.
One modern method ‘Foamed Concrete’ construction combines principles of structural masonry together with the advantages of light weight foam concrete. Foam concrete is prepared by aerating the concrete profusely as it is mixed to create a highly fluffy, lightweight substance. Building blocks and units made out of this material lead however to centralisation and are subject presently to patent laws.

Masonry when properly construct, possesses good resistance to seismic forces. Bad construction, however, means disastrous consequences. Improving the rigidity of load bearing masonry by way of three RCC bands one each at plinth, lintel and roof levels, is the most common technique employed in a country’s earthquake resistant housing programmes today. These houses, when constructed under supervision can resist earthquakes of moderate intensities quite efficiently.


Creating better resistance to earthquake today involves access to steel and cement concrete if not to ultra modern aerated concrete blocks. There have been several attempts at local levels to make use of bamboo and mud instead. These attempts have not all stood the test of time; most of them have not got the chance to face further quakes of high magnitudes - but these attempts have always met with criticism by the scientific fraternity. In our rural housing, local materials have to play an important role. Even poor man’s materials can be used to provide extra strength to a dwelling unit with incorporation of a few simple engineering principles. Total safety can not be assured even by use of high-technology - but all dwelling houses, big and small, can be made safer

Acknowledgement: Narayan Sarma; Development Alternatives; Newsletter, January 1996. Go to top...

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