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TARA Ferrocement Roofing Technology

 

TARA Ferrocement technology package for roofing uses state of-the-art design principles to manufacture reinforced shells. Commonly called channels they are produced on specially designed vibrating tables and profiled moulds. The production system is uniquely tailored to provide special end details, consistent shape and thickness; all crucial for high performance the channels made with an optimised proportion of cement, sand and water. They have a very high density, are impervious to penetration of water and provide high structural strength. Ferrocement roofing technology offers a viable alternative to conventional flat roofing systems such as reinforced cement concrete, reinforced brick cement, sand stone, etc. in both rural and urban areas of the country.

Product
Ferrocement roofing channels have a uniform segmental profile; they are 2.5 cm thick and 83 cm wide. Maximum length of mechanically produced channels can be upto 6 metres.

Ferrocement roofing channels are manufactured using designed mix of cement, sand and water to give high strength mortar that is reinforced with a layer of galvanised iron chicken wire mesh of 22 gauge and tor steel bars of 8-12 mm diameter provided in the bottom nibs of the channel. Ferrocement roofing channels can be safely transported for the application after a curing period of 14 days.

Brief production process
The mechanised system of production uses a vibrating table and profiled steel shell moulds. The production yard consists of a vibrating table positioned under a gantry system 6.5mts in width the gantry is fitted with a chain and a pulley system for ease of handling of cast moulds. A production team consisting of 2 mason, 12 unskilled workers and a supervisor can produce upto 15 channels of 3.0-m length each in 8 hours operation.

The moulds are cast using the designed mortar and the filled moulds are lifted from the vibration table using specially designed lifting frame and steel tongs. Before demoulding, these moulds are kept undisturbed for 24 hours till the freshly cast channels achieve minimum strength. Finally these channels are stacked for water curing for minimum 14 days before they can be used for construction.
 Advantages
of TARA Ferrocement channels

Fast construction prefabricated channels enable to construct a roof in just 3 days
No shuttering required, unlike in-slab slab casting
30% cost saving over RCC roofing
Less dead load on the walls
High strength to weight ratio
Appealing aesthetics - elegant profile and uniform size

Areas of Application
Ferrocement roofing channels, offer unmatched speed of construction and offers a vast range for flat roof application.

Residences
Primary schools, and other community buildings
Porticos, verandahs and garages
Industrial sheds, Workshops and godowns
Farm houses and semi-covered structures


Development Status

Commercialized  


Technical Data

Specifications of the channel Length - 3.05m and 4.6m (maximum upto 6.05 m) Clear bay width 0.75m, total bay width 0.83m Profiles as per rise of the arch - 290mm and 150mm
Annual production 3000 No. of Ferrocement channels
Land requirement Total 2500m2 for casting, demoulding , curing, stacking and movement space,250 m2 of covered working space
Electricity requirement 10 KVA
No.of jobs created 10 (1 supervisor, 1 skilled, 8 unskilled)


 

Economic Data

Infrastructure cost for office and workshop (includes: Working shed, office space, cement godown, facilities-electricity and water)   Rs 240,000
Equipment (with 1machine, 10 No moulds) (vibrating table with vibrators, moulds, lifting frame, a pair of tongs and transfer trolley) Rs 384,000
Gantry system cost (in a mechanized system) Rs 125,000
Transportation and insurance (in India Rs 12,000
Installation and know how transfer Rs 50,000
Total (package with hydraulic machine) Rs 8,11,000/- (US$ 16,220)
These cost do not include cost of land, as it varies considerably from place to place)

  

Business
Ferrocement technology is a highly profitable business for small scale building material producers and construction companies. To start the enterprise with a set of 10 moulds, require a total investment of Rs. 8,11,000/-. This semi-mechanised production system assures a turnover of Rs 29,50,000/- per annum, which yields more than 20% recovery on the investment within one year of operation. Moreover, within 2 yrs of operation, by investing into 5 extra moulds, which cost Rs 1,45,000, the turnover of the production unit can be increased by 1.5 times, producing 15 channels per day. This increase in productivity involves minimal increase in labour requirement without any investment on infrastructure. The equipment is supplied by TARA (Technology and action for Rural Advancement), a leading sustainable technology marketing organisation

Transfer forms

Equipment, Turnkey basis


For further information, please contact:

Mr. Subroto Roy
Senior Business Development Executive
Development Alternatives
B-32, TARA Crescent
Qutab Institutional Area
New Delhi 110016

Tel :     91+ 11+ 2696-7938, 2685-1158
Fax :    91+ 11+ 26866031
Email : tara@devalt.org
             sroy@
devalt.org
URL:     www.devalt.org
 

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