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Former rugby league star Matthew Ridge has been hit by a leaky building claim which may have implications for anyone who has sold a new house since the crisis emerged.

Ridge is being sued by a man who bought the swanky house in St Marys Bay he and ex-wife Sally built between 1990-1999. The matter is now before the High Court at Auckland.

The claimant paid $2,750,000 for the 794sq m three-storey designer mansion in 2001. According to Auckland City Council documents lodged in August, the homeowner now faces a bill of $650,000 to reclad the existing building. These documents show "external moisture" has caused problems on the 250sq m third floor.

Auckland District Council files show the Ridges gained all the necessary building consents at the time of construction. But the construction company they used, Black Rock Construction Ltd, went into liquidation in 2002, leaving the couple potentially liable for the "leaky home" repair bill.

The present owner told the Herald on Sunday the home was diagnosed as a leaky building by an expert about nine months ago. Occasionally, after heavy rainfall, water would drip inside.

The homeowner said repair work would start shortly and his family would move out for several months while the work was being done.

He refused to say what sort of renovations he had made to the house himself over the past six years, but denied a lift had been installed.

He said he was taking legal action to recover the cost of the repair work.

"It's a private matter - nothing to do with the public," he said. "We are physicians who have moved here from the United States. We are a private couple and we relish our privacy. We bought the home off the Ridges - we had no idea who they were. They're not a household name in America."

Both Matthew and Sally Ridge were similarly disinclined to discuss the case. "I'm sorry but I've got no comment about the whole thing," said Sally, who is engaged to former cricketer Adam Parore.

Martin Evans, president of New Zealand Property Investors Federation, said a clause in standard sales and purchase agreements was being used by lawyers to put the responsibility of a leaky home on the previous owner.

"A statement from MP Bob Clarkson said leaky homes... according to real estate agents, can cost unwitting house sellers hundreds of thousands of dollars many years down the track," Evans said. "One woman built a house in 2002, lived in it for two years, and sold it in 2004. In 2007, the new owner found the house was leaking and sued the original owner for repairs. She sold her house for $270,000 and now faces a repair bill of $210,000."

It means if a house passed its council building consent obligations when built, and the house was sold on twice, the previous owners, who might not have built the home, could be held accountable.

"The clause was originally included in the contract to cover new owners against buying a house that had been extended without consent," Evans said. "Lawyers are now using it to attack previous owners for leaky home liability when the builder has gone broke or overseas."

John Gray, an advocate for leaky building owners, said if a previous homeowner had any control over the house building, he or she could assume some liability to any or all subsequent owners.

"This is a huge risk many owners aren't aware of. Any owner building a house needs to make sure they get professionals with contracts in place, so the home is built in accordance to the code and is going to meet the performance and durability requirements long-term."