Master Builders ACT executive director John Miller said the Australian National University's biosciences building won because of its complicated construction and the demands it placed on the people involved.

''There was a lot of technical difficulty involved in that,'' he said. ''It was very complex and is quite unique and very technical.''

It was among 68 winners - and five distinguished merit awards - presented at a black-tie event held at the National Convention Centre last night, attended by almost 1500 people.

The title of House of the Year went to a luxurious two-storey property in O'Malley that could easily belong in Hollywood. The house was built on a steep block.

''It was a feat of the highest quality,'' Mr Miller said. ''A lot of technical difficulty was involved - it was a collaboration of people who brought it to the standard it is in.''

The awards saw more than 250 original entries submitted, which were self-nominated by Master Builders' members, and then judged over a six-week period.

Eight teams, each with three judges, consider elements such as quality, innovation, technical difficulty and environmental aspects.

''It's a number of factors,'' Mr Miller said. ''[But] ultimately it's on the quality in the finished product.

''The people involved [with the winning projects] have got to demonstrate skill,'' Mr Miller said.

RAM Constructions won the Chief Minister's Affordable Housing Award.

Other winners included Modern Plaster for Supplier of the Year, J & J Interiors for Subcontractor of the Year, Steven Gavagna of Goodman Law for Professional of the Year, Rob Bobeldijk of Complete Constructions for Young Commercial Builder of the Year, Brian Lawrence of MBA Group Training for Youth Participation and Training, Jamie Gianchou for Apprentice of the Year, Trystan Warn for Cadet of the Year and Rod Jenkins for Emerging Residential Builder.