The upgrade, designed to increase the variety of events held at Olympia, includes redevelopment of the West Hall, within its existing footprint, into a two-storey 8,361sqm exhibition facility by adding a floor, and creating links to the Grand Hall and Olympia 2 behind the restored façade.
Olympia 2 will be reconfigured to provide more efficient servicing arrangements and improved connectivity with the rest of the facility.
Nigel Nathan, group managing director of EC&O Venues, said: "Our development plans aim to respect the fabric of the historic building whilst also making the internal space easier to access and more flexible for organisers to use.
"Before we submitted our proposals we consulted widely with the community and have been pleased with the response to our plans. We believe the investment will bring in business, new jobs, and continued prosperity for Hammersmith and Fulham, benefiting the whole of West London."
Capital & Counties Properties (Capco), which owns EC&O Venues, is set to commence construction work on the site in early 2011, throughout 2012.
The work will be phased to allow the exhibition and conference business already operating at Olympia to continue throughout.
The cost of these works were included within the previously announced £20m of capital allocated to Olympia and will be funded from existing Capco cash resources.