Ius died on Thursday 3 July, hours before he was to learn if he was to become president of the organisation.
He was one of two candidates – the other being Australian Louise Cox – vying for the presidency of the UIA, a position assigned at the end of the conference, which closed on Friday (4 July).
Members of the assembly, which included architects from around the world, paid their respects to his wife Caterina, who gave a moving address, reading the speech that Giancarlo was to have given to the assembly.
RIBA president Sunand Prasad said the assembly was 'in complete shock' at the news.
Ius was born in Zoppola in the providence of Pordenone, Italy in 1953.
As well as heading up his respected Pordenone-based practice, he was known for his commitment to salvaging and restoring buildings damaged in the 1980 earthquake in the Irpinia region of Italy and his tenure - from 2005 - as vice president of the UIA.
At the time of his death Ius was also head of the Italian delegation to the ACE (Architects' Council of Europe).