Fletcher Building chief executive Ross Taylor. Photo: RNZ / Cole Eastham-Farrelly
Shares in Fletcher Building plummeted 11 percent, wiping about $450 million from its market value as investors digested competing claims over a leaky pipes issue in West Australia.
The top-10 listed company's shares plunged as much as 14 percent when trading resumed after a three-day halt.
The price gyrated through the session but closed down 55 cents at $4.33.
Devon Funds head of retail Greg Smith said the company had put up a credible reply to the Australian building firm's charges, but the sharp price fall was no surprise.
"The market has decided to shoot first and ask questions later."
A Perth based building group, BCG, has claimed the pipes are defective and the problem is extensive throughout Australia, with a potential cost of as much as $1.9 billion.
Investment analysts have said the matter is most likely headed to the courts, and the final cost for Fletcher Building may stretch into the hundreds of millions of dollars.