Downer EDI Work's new South Island head office in Green Island.

The new $3 million offices for Downer EDI Works are expected to be completed by late-February and are an extension to its existing Green Island site, which is the company's South Island head office.

Three houses were purchased and demolished on Main South Rd to make way for the two-storeyed office, being built by Stevenson and Williams, and which has about 1500sq m of floor space.

Downer's general manager of southern operations, Mark Keane, said of the total 150 staff at Green Island, up to 60 would be accommodated at the new offices and about 25 staff from Downer Engineering at Parry St would relocate to the workshops for the scheduled move in February.

Nearby, Dunedin gas fire manufacturer Escea New Zealand has invested $4 million in a purpose-built manufacturing plant where its 44 staff will move to next week, from Devon St.