A construction materials "crunch" prompted New Zealand's biggest listed retirement business to take matters into its own hands.

Ryman Healthcare has leased an existing pre-cast concrete panel-making plant at Wiri in South Auckland and a spokesman said that meant it was less reliant on suppliers.

A material supply shortage prompted the move, after construction of a new North Shore village ran nearly two months behind.

"We are leasing the precast plant in Wiri so the cost is not great - it is an existing facility. We wouldn't put a figure on it. We plan to employ between eight and 12 steel fixers and formwork carpenters on site and the plant has the potential to produce eight new panels a day or 40 new panels a week when it hits full capacity," the Ryman spokesman said.


"We have done this before. We manufactured our own precast panels for the construction of our Edmund Hillary village during the last Auckland building boom, so we know what's involved. We put a plan into place to start manufacturing when we realised the extent of the supply crunch.

"It gives us the ability to control our own destiny rather than rely on suppliers who are stretched. Our suppliers have been great and done their best to accommodate us, but I think if you talk to anyone in construction you will hear a similar story."

Quotable Value said construction costs were rising fastest in Auckland and Christchurch.

QV spokeswoman Andrea Rush said the average cost of building a standard 140sq m, three-bedroom one-bathroom home was $266,000 in Auckland, $252,000 in Wellington, $272,125 in Christchurch and $248,500 in Dunedin.

"The highest increases in costs have occurred in the large house category between 200-600sq m with the price of building a house this size up 34 per cent since the previous building boom in the lead up to the peak of 2007," Rush said.