Opened in May, the Heritage Queenstown Icon Conference Centre was designed by architects Warren and Mahoney.
When presenting the award, the judges complimented Icon's "integrated" placement between the existing hotel wings and its meticulous detailing.
"Everything has been well thought through in this lozenge-shaped conference space between two hotel blocks, also originally designed by Warren and Mahoney," the judges said.
"Meticulous detailing, including a carpet with lines measured so that staff can line up seating with military precision, is balanced by the use of curved walls and glass."
The two-storey conference centre is built on the lake side of the hotel, making the most of mountain and lake views.
The dividable conference room caters for up to 200 people seated theatre-style, with pre-function trade display space, display vehicle access and a roof-top deck overlooking Lake Wakatipu for outdoor events.
For the judges the project's success lay in the "flexible uses the spaces afford, both indoor and outdoor".
"Conference delegates will be tempted out on to decks to enjoy the scenery and most chefs would die for the full commercial kitchen," the judges said.
The building also has a brief to be environmentally sustainable - an aspect Warren and Mahoney have become known for.
"The award is a great honour and endorses what many of our conference and wedding clients to date have told us," Heritage Queenstown general manager Carey Norton said.
The hotel is a past winner of the New Zealand Tourism Industry awards in 2005 and 2006 and won the 2007 Queenstown business award for accommodation excellence.
It was also Queenstown's first to be Green Globe benchmarked.
