New Zealand's biggest builder is about to start a $40 million makeover at its own global headquarters, after buying its headquarters back from Tauranga's Carrus Corporation.

QV records showed Fletcher sold the 1960s building in 2009 for $36 million but had to pay $6.5 million extra to buy it back only five years later for $42.5 million.

Fletcher Building chief executive Mark Adamson spoke at Wednesday's media briefing after the annual result on plans for the Penrose site where he said buildings did not entirely suit the company's needs.

Fletcher has bought back control of its seven-level brown Fletcher House at 810 Great South Rd and will build a one-level structure between that and Jack Smith House, headquarters of Fletcher Construction, at the neighbouring 816 Great South Rd.


Adamson said the new building would be for staff who now spread across the city, as well as for meetings and conference space.

"This is the biggest area we've got," he said, indicating the small room on level seven of Fletcher House. The business needed more meeting and conference space as well as more office area, he said.

Internal walls have been demolished and open-plan offices created on levels three and four of Fletcher House but plans are for refurbishment of the entire building, a partial prompt for the $1 million sale of 55 Fletcher Trust collection art works. Adamson said his own office was part of the open-plan drive.

Fletcher employs 18,750 people around the world.