MUMBAI: Kumar Mangalam Birla, chairman of the $41-billion Aditya Birla Group, outbid rivals to emerge as the highest bidder for the sea-facing Jatia House in Mumbai’s largest-ever property deal. Birla agreed to pay Rs 425 crore to buy the two-storey house in the city’s tony Malabar Hill area on Monday after a day-long auction.Birla pipped five bidders, including Ajay Piramal's Piramal Realty, for the 30,000 sq ft bungalow. Birla has already paid a 10% token of the entire amount. This will be the most expensive real estate transaction in the city, outpacing Sajjan Jindal'fs purchase of Maheshwari House in 2012 for Rs 400 crore and industrialist Adi Godrej's bid for Mehrangir, the iconic bungalow of Homi Jehangir, father of India's atomic energy programme. Godrej paid Rs 372 crore for the bungalow.Bishops Gate, a five-storey residential building co-owned by Standard Chartered and the Hong Kong and Shanghai Banking Corporation ( HSBC ) in upscale Breach Candy area in the city, was sold for Rs 272 crore to Peninsula Land, an Ashok Piramal Group company, in 2011. Jatia House is owned by the MP Jatia Group which also includes Pudumjee Pulp and Paper.The Birla family, currently staying at Mangalyan at Altamount Road, will retain the new bungalow for personal use, officials said. A number of industrialists who have been born and brought up in south Mumbai, now want to have bigger spaces as their children grow up, officials said on condition of anonymity.The deal will be concluded in next one month. Kumar Mangalam Birla was unavailable for comment. Repeated calls made to reach Arun Jatia went unanswered. Transaction advisor JLL India declined to comment for the story.Jatia House is among the most sought after residential location in south Mumbai, an upscale property market which is much sought after by the swish set for property deals. The Jatias purchased the bungalow in 1972 from Meher Cawasji Vakeel.