Simon Hughes MP opened the new Glass and Glazing Federation offices in Ayres Street on Thursday afternoon.
The federation was previously located at 44 Borough High Street. The new building, refurbished and given an appropriate large glass frontage, preserves a mosaic on the outside back wall which is a feature of the adjoining Red Cross Garden.
"Single glazed windows were not the best advertisment for our industry" said the president Robert Aitken as he recalled the federation's former address which was a listed building. "We now have a building which is designed for the industry products."
He added: "A major drive of the federation continues to be promoting the benefits of energy efficient windows and glazing."
Simon Hughes said: "You are going from a building in a very important street to a building which has considerable historical importance. Octavia House is named after Octavia Hill, a great Victorian social reformer and founder of the National Trust."
The Mayor of Southwark, Cllr Jeff Hook, was also present at the opening ceremony.
The GGF bought Octavia House last year for £1.8 million. Its old building opposite the war memorial in Borough High Street has been sold and is now subject of a planning application to convert the ground floor into a shop or restaurant.
The Glass & Glazing Federation is a successor to the Flat Glass Association which incorporated the Insulating Glass, Safety Glass and Glass Benders Association. The original body was the 19th-century Glass Merchants Association.
Vigorous campaigning by Bankside Open Spaces Trust, the Octavia Hill Society and others led the GGF to revise its earlier plans for the building which involved repositioning the historic mosaic known as 'The Sower' which was installed by Octavia Hill in 1896.
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