The estate was built at a cost of $186 million and comprises 6,200 flats designed to house some 46,000 residents based on the Housing Authority's former space allocation standards of 35 square feet per person. The "authorised population" of Oi Man Estate has since been revised to 18,900 residents. It was designed by Housing Department architects, and followed the 1970s estate design innovation of being planned as to "provide every convenience for its residents from banks, markets to barbershops." To this end the estate opened with a three-storey air-conditioned commercial complex, a market, and cooked food stalls.
The British Hong Kong Government admired the construction of the estate because its construction showed improvements in public housing standards in Hong Kong. Oi Man Estate was on the itinerary of Queen Elizabeth II when she visited Hong Kong in 1975. Leader of the British Conservative Party Margaret Thatcher also visited in 1977 and toured Tak Man House, commenting on the modern living conditions, cleanliness of the block, and the cool air circulating within the Twin Tower block's atrium.