The 147-year-old Shapoorji Pallonji Group, which has built Mumbai's high-end buildings like that of RBI, is now planning to expand its affordable housing arena across India, apart from Kolkata. The firm's real estate company Shapoorji Pallonji Real Estate (SPRE) has ventured into its first affordable housing project in Rajarhat, Kolkata, with SP Shukobrishti, and plans to extend this drive to other cities.    The firm says that there is a huge market in the affordable segment and are looking at it seriously. The firm said that it entered the affordable housing segment in 2007 to cater to the highly under-serviced market and satisfy the social need of providing low-cost housing.    Shapoorji Pallonji is now looking to considerably expand its footprint in this segment further across the country. The company is examining this business model for Mumbai’s MMR region and the outskirts of Bangalore, Pune and the NCR.    In Kolkata, the company has rolled out 1,500 housing units of 1-BHK (bedroom, hall and kitchen), measuring 320 sq ft, at Rs 4.6 lakh, and 2-BHK of 480 sq ft at Rs 8 lakh last month. In all, the company has launched 7,700 housing units in the first three phases on a 150-acre site in the city. This Rs 2,700-crore project has been jointly developed with the West Bengal Housing Infrastructure Development Company and will eventually comprise 20,000 apartments. Of these, 12,000 are meant for the low-income group and the rest for the mid-income category.