Whittaker cut the ribbon with Lewis - the club’s longest serving life member - in support.
Although Whittaker never played for the club, he was a long-term coach of junior grades and a committee member when the previous clubrooms were opened in 1978.
"Dad was one of the mainstays behind building the clubrooms that will be knocked down. They came up with ‘buy a brick, buy a chair or buy a table’. That’s how the club was formed really,” said Whittaker’s son, fellow Hornets stalwart Jeff.
"It was a proud moment to cut the ribbon.
"It was great to see so many old players, old coaches, managers and trainers. It was a very special day for the club."
The $2 million project - financed by an insurance payout, plus support from the Lottery Grants Board, Air Rescue & Community Services and Kiwi Gaming Foundation - was more than a decade in the making.
And although rugby league is the focal point, other codes are expected to utilise the facility.