Sydney’s most famous Cantonese restaurant is celebrating 30 years by launching a new level of dining at its bustling late-night Sussex Street restaurant, one it says has a greater focus on wine and more considered service.

Golden Century Wine Bank is a 180-person private dining space on level three of the restaurant, and it’s now taking bookings for parties of six to 180 people. The new level has its own purpose-built kitchen, and the space can be configured into differing-sized private rooms (up to eight rooms) where diners can order from an a la carte or banquet menu (available from $128 to $188) or can customise it to suit their needs. That means if you want to have a midnight XO pipis party – a dish that’s been on the menu since the early 1990s – or choose a five-course seafood feast, you can.

As the name suggests, wine will be a big focus in the new space. Jon Osbeiston, who is leading the wine program, has pulled together more than 1000 wines, which are stored in a wall lined with Vintec fridges. In the new cellar there’s an additional 600 rare and vintage wines, and if you’ve got a bottle of something special you can use the space to cellar your own wines. There is also an extensive whisky and spirits collection from around the world.

“At Golden Century Wine Bank we want to elevate Chinese food and have amazing fine wines to match,” said owner Eric Wong of the Golden Century Group in a statement. “We’re excited to have a bottle of wine for every menu item and we chose the name ‘Wine Bank’ because in Cantonese it sounds like ‘prestige collection’, and that is what we have on level three.”

Eric with Linda Wong opened their first seafood restaurant in Hong Kong in 1979 before migrating to Australia and launching Golden Century in Sydney. In its three decades it has built a huge following and has [opened another restaurant, The Century in the Star casino. Last year the group announced it will launch XOPP in August this year. The modern Chinese restaurant will be at the coming-soon six-storey Darling Exchange designed by Japanese architect Kengo Kuma.

It will be run by their son, Billy Wong (who also runs the Star restaurant), who last year chatted to Broadsheet about the news. “It’s a huge credit to mum and dad – the work they’ve put in over the years. There is a legacy they’ve built and a reputation around the brand that didn’t happen overnight. That goes to the team as well – a lot of people working in the restaurant for decades, that to me are uncles and family.

“When the opportunity came up to open a new restaurant, the idea was [about] taking the old and making it new. It’s the next generation of the legacy and the story,” he says.

The couple’s other son, Alex Wong, is behind the design. His Hong Kong-based Paring Onions did the interior design.

The Wine Bank build wasn’t easy. After a builder walked away from the project construction company Schiavello took over, telling Broadsheet the existing building restrictions meant new construction techniques were needed. Custom cranes and platforms were developed, and the team built the largest roof hatch in the Southern Hemisphere to bring in 15 tonnes of steel. It all had to be done without disrupting service below – which continued from noon to 4am every day.

Golden Century Wine Bank is open seven days at 393–399 Sussex Street, Sydney.