Russells Construction has completed a £2.2m refurbishment of a 35,000 sq ft office building at Atlantic Park in Sefton.
The project received £3.1m funding from the European Regional Development Fund and a further £1.6m from the North West Development Agency.
Ian Steele, partner at GVA, the letting agent for the scheme, said: "Caspian House is the only office scheme to have been speculatively developed in the decentralised Merseyside office market during the last 18 months.
"Although this is a remodelled building, Caspian House competes directly with new build space and offers occupiers the unique opportunity of acquiring 35,000 sq ft on a single floor plate.
"Fully remodelled to Grade A standards, Caspian House represents excellent value for money in a well-located, quality business park environment."
The former Rolls-Royce plant, renamed Caspian House, is part of the 800,000 sq ft mixed use business park in north Liverpool.
Industrial Securities, the development manager acting for land owners Royal London Asset Management, managed the programme of works. Russells Construction was the contractor and took six months to complete the work.