Methamphetamine contamination is only one reason Housing New Zealand is cleaning up and selling a house in Newton Rd on the outskirts of Whangarei.

The Newton Rd property was sub-let by the state housing agency to a health provider group which transferred to another Housing New Zealand (HNZ) community group house earlier this year.

It was the scene of an extensive decontamination operation last week.

HNZ confirmed seven of its Northland houses had recently tested positive for methamphetamine, above the Ministry of Health guidelines of less than 0.5 micrograms per 100cm2, and were being cleaned up.


"When we sell or acquire properties, standard procedure is to carry out methamphetamine testing as part of that process," the agency said.

"In Northland at the present time we currently have seven properties that have tested positive and are in the process of being decontaminated so they can be returned to the letting pool and relet."

HNZ had 24 Northland houses infected by methamphetamine in the year to May, and expected the number, and clean-up cost, to rise as it started testing all its houses at each change of tenant. In May this year, before that regular testing regime began, HNZ spent $231,361 decontaminating 13 Northland houses over the last three years.

HNZ cited privacy reasons in declining to name the community group that was last to live in the house in Newton Rd, Maungatapere.

The state house agency is not the only rental manager or property owner being forced to deal with a drug problem, the effect of which is as hard-hitting as the leaky home disaster. Whangarei property managers say the methamphetamine contamination problem does not just belong to social housing or quick-turnover properties but is widespread.

Apart from houses being used as a lab to cook up the drug, also called meth or P, there was no "typical" P-smoking tenant, said Allan Inglis, principal of Northland First National. The company's experience indicated more people smoked P inside houses than smoked cigarettes - or, at least, tobacco smokers did it outside now.

Property managers were well schooled up on the methamphetamine scourge and were trying to manage the risks, but many believed the Ministry of Health's bottom line for contamination should be raised, he said.

Like tobacco smoke, P smoke permeates "every nook and cranny".

Landlords can install alarms that alert a monitor centre which then refers it to police when someone lights up with P, but more commonly a property is tested when a tenant moves in and when that tenant leaves, Mr Inglis said.

It was also common practice for houses being sold to be tested.

Whangarei rental manager Judy Morgan has called for a register naming tenants who "poison" homes. She also said tighter controls around testing standards need to be established and the limit raised.

Ms Morgan, the managing director of Property Management and Rentals, has asked the Government to draw up a code of regulation for those doing the testing.

The Ministry of Health offers guidelines, not standards, and the methods used by testing agencies differed.