Meth contamination: the 2026 rules

The two numbers that matter

Everything in this area now hangs off two figures set by the Regulations.

15µg/100cm² — micrograms per hundred square centimetres — is the contamination threshold. Any part of a property above it is contaminated and must be decontaminated until it is at or below that level.

30µg/100cm² is the habitability threshold. If any part of the property is above it, the property is uninhabitable as a matter of law. That is not an opinion a tester offers; it is the maximum inhabitable level set out in legislation.

Room by room, not whole house

This is the change that most affects what a contamination event actually costs you. Contamination is determined on a room-by-room basis. Tenancy Services gives the example in its own words: if a bedroom is above 15µg/100cm² but the kitchen is below it, only the bedroom needs to be decontaminated. A single high reading no longer condemns an entire house.

What you must and must not do

Landlords must not knowingly rent out a property contaminated with meth, and must decontaminate before re-letting. If a tenanted property is found to be contaminated, you may continue renting it only while it is being decontaminated. Renting out a contaminated property risks breaching not just the Residential Tenancies Act but potentially the Building Act 2004 and the Health Act 1956 as well.

Testing: screening versus detailed

A screening assessment detects whether residue is present and whether more testing is needed. Anyone can carry one out at any time — tenant, landlord or professional — provided it uses an approved method and follows the instructions.

Detailed testing confirms how much contamination there is, where it is, and whether decontamination is required. You are required to arrange it in two situations:

• Police or a local Council notify you that meth has likely been manufactured at the property; or
• a valid screening assessment by anyone shows at least one area above 15µg/100cm², and you are made aware of the result.

Detailed testing must be done by a qualified professional, and — a detail worth noting if you are being offered a package deal — that professional must not be the same person who will carry out the decontamination.

Approved and unapproved methods

Screening and detailed testing must both follow NZS 8510:2017, as modified by the Regulations. Approved methods are individual sampling, laboratory composite testing, and validated screening test kits.

Two things are not approved: field composite tests, which combine swabs from several locations and so cannot tell you which room is actually contaminated; and unvalidated testing kits, which may react to other substances or give inconsistent results. Given that the whole regime is now room-by-room, a test that cannot identify the room is of no use to you.

Your notice and disclosure obligations

If you carry out any testing during a tenancy, two duties attach immediately. You must give the correct notice of entry before you or your contractors go in. And you must provide the test results to the tenants within 7 days of receiving them.

Failing these obligations exposes you to exemplary damages of up to $7,200, and in some situations pecuniary penalties of up to $50,000. This is the part of the regime with the sharpest teeth, and it is entirely within your control.

Ending a tenancy over contamination

Where any part tests above 30µg/100cm², the property is uninhabitable and either party may end the tenancy, provided they are not at fault for the contamination. The landlord gives 7 days' notice; the tenant gives 2 days'.

There is an important exception. If the contamination is confined to a remote and inconsequential part of the property, nobody can end the tenancy immediately. A part qualifies only if it is physically separate or can be closed off so contamination does not spread, and the rest of the property can still reasonably be used as a residence without it. Where that applies, the rent must reduce to reflect the lost access, and either party may apply to the Tenancy Tribunal, which may end the tenancy if it would be unreasonable to require you to decontaminate that area or unreasonable to require the tenant to stay even at a reduced rent.

Recovering from the tenant

A tenant who smokes, sells or manufactures meth in a rental is using the property for an unlawful purpose, which breaches the Act, and is also breaching the obligation not to damage the property. The Tenancy Tribunal may order a tenant who used the property for an unlawful purpose to pay damages of up to $1,800.

Set that number against the cost of professional decontamination and the point makes itself: recovery from the tenant is not where this gets paid for. Your policy is.

Where insurance sits

Meth cover is a sub-limit, not a general benefit, and it varies. Tower publishes up to $30,000 for meth contamination damage on Landlord's Plus. That is Tower's own published summary and its wording governs.

The genuinely useful question for any landlord right now is not “am I covered?” but “does my cover still line up with the 2026 thresholds?” Policies written against an older understanding of contamination levels may respond differently than you expect. That is a wording question, and it is exactly the sort of thing worth putting to a broker who reads them for a living.