Auckland tufting operation relocation will result in some redundancies.
Mr Timpson formed the carpet maker in 1972 with Grant Biel.
The maker of Bremworth carpets says profit fell to $1.4m in the six months ended December 31, from $3.5m a year earlier.
He replaces Victor Tan, who is retiring after 28 years with the firm.
Mr Tan joined the Auckland-based company in 1984, the same year it listed on the New Zealand stock exchange.
The loss comes after a profit of $18.2 million a year earlier.
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