"That's fantastic. They've only been out for a month or so and now they've done this," said one construction analyst. "Obviously they had the cash and 3i wanted a quick sale."
The Prowting family fought off interest from several housebuilding firms, including Wimpey, after the £66m-turnover firm was put up for sale by 3i.
Banner chief executive Richard Werth said the high level of interest illustrated the market's confidence in Banner.
"It provides us with long-term stability of ownership and the necessary resources to take Banner forward," he said. Banner was taken private in 1998 by a management buyout team with the backing of 3i, but the venture capitalist decided to pull out this year.
It provides us with long-term stability and the resources to take Banner forward
Richard Werth, chief executive, Banner Homes
The deal is the latest in a series in the housebuilding sector and industry experts predict that more will take place as the City increases pressure on firms to consolidate further.
The Prowtings takeover of Banner is the second major deal involving unlisted housebuilders this week. Building understands that Country & Metropolitan is about to close a deal to take over a privately owned firm in South Yorkshire.
It is believed that C&M's target is NorthCountry Homes Group, which has five subsidiaries. Industry sources expect the deal to be announced within the next week. C&M's shares were suspended in May after it announced that it was in merger talks.