The Edinburgh Architectural Association (EAA) has given the building - which was designed with RMJM - the Centenary Medal, the highest accolade the organisation can hand out.
EAA president Colin Gilmour said he was delighted to give the award to the building's architectural team.
He said they had 'the vision, courage and stamina to create a masterful piece of architecture, which all of Scotland should be proud of'.
The judging panel - comprising professor Robin Webster of Glasgow-based Cameron Webster Architects, Eelco Hooftman of Edinburgh-based landscape architect Gross Max and Ian Springford of Ian Springford Architects - was unanimous in its decision.
The Centenary Medal was introduced in 1957 to mark the EAA's centenary, and is awarded in recognition of outstanding architectural merit in a building or group of buildings.
As the medal aims to represent the pinnacle of design achievement, it is not awarded on a frequent basis and has only been presented on seven occasions since its inception. The most recent winner was the Museum of Scotland Extension by Benson & Forsyth in 1999.