A new library and cafe will open in County Hall in Trowbridge next month, as the first phase of Wiltshire Council’s £22 million refurbishment is completed.

The library, designed to be bright and airy, will open into the reception courtyard, which has been covered over with a bubble roof based on Cornwall’s Eden Project.

It opens on September 12, but staff will begin moving into the building from other council offices later this month, before the refurbishment of the rest of County Hall gets under way.

Next to the library are a relocated registry office and a public cafe.

The building has been designed with a heat pump system to improve energy efficiency.

Project manager Mark Butt said: “Phase one, refurbishing the newer 1970s building and courtyard, is virtually finished now; on time and on budget, so we are very pleased.

“One of our aims has been for the building to use 40 per cent less energy than it used to, partly just through good design.

“We have been building and upgrading services and systems to make them more efficient and we also have a highly energy-efficient heat pump system.

“We haven’t included any photo-voltaic panels or biomass plants or anything like that, but this system is very flexible if we want to make improvements in future.

“The next stage, over the next couple of months, will be to move staff out of the older part of County Hall and start bringing that up to date.”

Work, carried out by Kier Construction, has involved more than 30 contractors and suppliers from Trowbridge and the surrounding area.

The council plans to cut its 95 existing buildings to just four main hubs, including County Hall, reducing maintenance and energy costs, and claims the project will help save more than £85 million over the next 25 years.

Offices to be closed include the Bradley Road building in Trowbridge and temporary offices on the George Ward School site in Melksham.

The project’s second phase is due to end next summer.