Builders' insurance counts cost

By KEVIN TAYLOR

Half of all claims to the Master Builders' Federation's own insurance company are for water damage to houses.

In the past five years the federation's Guarantee Company had spent $1.8 million fixing faults on homes its members built - half relating to water getting into the house.

The Weekend Herald on Saturday revealed the industry's alarm at a growing number of timber frames rotting in new houses after untreated kiln-dried timber was used and new "chilly-bin" claddings leaked.

Federation chief executive Chris Preston yesterday revealed the extent of the problem, which he said was eroding the building industry's reputation.

The Guarantee Company dealt with 35 to 50 claims a year, most of which were for water damage.

The federation's 1800 members build three-quarters of the 20,000 dwellings in New Zealand annually.

Not all water damage related to cladding failures - some was because of roof or other problems.

But Mr Preston said the federation and industry wanted a strategy to build houses that did not leak.

The Building Research Association has formed an industry-wide working group to solve the problem and the federation was part of it.

Mr Preston said adequate training for builders on the new construction systems was needed. Builders also needed to be registered so standards could be maintained.

As well, building standards had not been enforced.

Though local council building inspectors were rigorous, customers needed more inspections - especially for areas which could leak.

The Building Industry Authority, a crown entity that administers the Building Act and Building Code, said the working group would study whether the code was adequate.

Spokeswoman Christl McMillan said the authority did not know how big the problem was, and needed more research.

It had funded one study - a survey of nearly 300 pre-purchase reports on Auckland houses by inspection firm Prendos.

The survey showed that in the houses - built over a 90-year period up to 1999 - 60 per cent had claddings that leaked. Thirty per cent of the houses were built in the past 10 years.

Ms McMillan said more than half had a defect that could let in moisture, either through the cladding, windows, doors, or through defects in a deck or balcony.

The Timber Industry Federation blamed the claddings for letting water in, saying the problem was not with the timber itself. But other building experts claim it was unrealistic for houses to be completely watertight.

Epsom builder John Barrett said a lack of workmanship was to blame for the rot. He said many builders now used untreated kiln-dried bottom plates - the wood that sits between a wall frame and the concrete foundation.

Rainwater was soaked up by the plates during construction and building inspectors probed studs - not the plates - for moisture.

"What we are noticing is the complete lack of good tradesmen now," Mr Barrett said.

He blamed the previous National Government's dismantling of apprenticeship schemes for the problem, as well as increasing use of unskilled labour on worksites.