The Precast Concrete Building Technology can be efficiently and effectively used on various Affordable / Low cost Mass Housing Projects being planned by the present Government Policy "House for all by 2020.

Urbanization in India has generated huge demand for housing which neither the cities nor the housing sector is prepared for.

The Construction industry is facing problems such as shortage of skilled labor, poor workmanship, low Productivity & quality of construction plus time and cost overruns etc.

In order to cater the issue surrounds the shortage of affordable and low cost mass housing at a much competitive cost and on time schedule, it is imperative to adopt alternative construction system.

The large projects comprising of Townships, Mass Housings, IT/ITES parks and SEZs’ are of common occurrence these days and will only grow exponentially in the near future.

Precast construction revolution is under way in India, and soon it will be the major type of construction to be adopted in the construction sector of India.

Concept of precast ("Pre-Engineered Pre-Cast") construction includes those buildings, where the majority of structural components are standardized and produced in bulk quantity in plants at Project site or in a location away from the building site, and then transported to the site for assembly.

If full advantages of precast concrete are to be realized, then architectural Drawings is to be frozen first. Having philosophy of: Long spans, appropriate stability concept, simple design & details, element IDs, element geometry, reinforcement and strand details, concrete specifications, connection details, MEP Details incorporated with the layouts of each floor.

Designers should, from the very outset of the project, consider the possibilities, restrictions & advantages of precast concrete, its detailing remains in scheduling the elements to their respective molds, stockyard, trailers & transportation, Erection & installation by assigning particular dates for each stage & serviceability, before completing a design in precast concrete.

Low Cost / Affordable Housing Projects

o The Advantages that Precast Concrete Technology has to offer can be exploited to the fullest for Mass Housing Projects comprising of small, compact size apartments in large volumes.

o This Technology can be implemented on such Projects in two ways, 1. Site based precast Plant 2. Dedicated precast Plant

Site Based VS Dedicated Precast Plant

o The Site based precast plants form a lucrative option for Indian Market as the excise duty, which otherwise gets attracted from Factory made precast components, is saved.

o Anyhow for adopting site based plant, there has to be sufficient volume of construction to justify the initial cost of setting up.

o Also, such plants have lesser efficiency than state of the art plants for obvious reasons.

Structural Farming

The Structural Frame for such buildings using precast concrete technology is essentially a Load-Bearing type of construction (cross-wall frame) eliminating the ugly column & beam offsets inside the compact rooms. The flooring slab can be in the form of solid reinforced precast units of room size (for site based plant) resting on the load bearing walls on all fours thus eliminating the requirement of structural topping. In case of dedicated precast plants, the flooring units have to be in the form of precast planks of not more than 2.4m width from transportation constraint. For monolithic action, these planks need to be topped with cast in place structural screed.

Medium / High End Condos

The medium / large size apartments can be conveniently constructed using precast concrete technology by adopting precast pre-stressed hollow-core planks as flooring which have a large load / span carrying capacity thereby eliminating the need for load bearing walls between the rooms or even the apartments. By minimizing the need for load bearing walls, the interior layout of the apartment becomes more flexible; which is a strong sales point for such apartments. The elevation treatment of these buildings can be made interesting by adopting decorative precast walls / spandrels on exterior.

Swot Analysis - Precast Technologies

Strengths Speed, Quality, Economy Low Maintenance Seismic Resistant Quick Turnover of Money Universal Application

Weakness Lack of Awareness, Acceptability & Availability Resistance to Change, Fear of Unknown, Unfamiliarity of Architects and Engineers, Lack of Exposure to the technology in Technical Institutes Opportunities Huge Requirement of Affordable Houses, Shortage of Skilled Labor, Large Size Projects, Exposure to Global Market, Demand for Quality Construction

Threats Govt. Tax Policy, Lack of Govt. Support & Encouragement, Bad Past Experience with Substandard Technology & execution, Vested Interests, Lack of Standardization, Imaginary Problems.