Building inspectors say councils around the country have failed to prepare for a construction boom and hire enough inspectors.

Photo: RNZ / Eva Corlett

Last week, the Tauranga City Council pledged to buy the 21 properties at the failed Bella Vista development.

The city council had signed off on shoddy work that left the buildings too dangerous to live in.

Nick Hill, the chief executive of the Building Officials Institute, estimates there is a 10 to 15 percent shortfall of inspectors around the country.

"On the ground ... that lack of capacity is leading to an inability to conduct a thorough inspection in many cases," he said.

Mr Hill said the shortage is partly due to a skills shortage but also councils have been too slow to act.

"They should have been taking the right remedial actions and recruiting some years back," he said.

He said if it is not addressed, it could lead to another Bella Vista bungle.