A Tenant Reports Mould: What a NZ Landlord Should Do

Mould is the maintenance report most likely to end badly. The tenant believes the house is making them sick. The landlord believes the tenant dries washing indoors with every window shut. Both can be partly right, and a year later neither can prove anything, because the only record is a blurry photo in a text thread.

The duties in one screen

We cover the responsibility question in depth, including how to tell structural dampness from a ventilation problem, in who is responsible for mould in a NZ rental. This article is about what you actually do in the days after a report lands. Here is the short version of the law it rests on.

There is no section of the Residential Tenancies Act 1986 that says "mould". Three duties do the work instead.

The landlord must provide and maintain the premises in a reasonable state of repair having regard to age and character (s45(1)(b)), and must comply with the healthy homes standards (s45(1)(bb)). Two of those standards bear directly on mould:

• The ventilation standard: openable windows in living rooms, dining rooms, kitchens and bedrooms, plus extractor fans venting outdoors in rooms with a cooktop or a shower or bath.
• The moisture ingress and drainage standard: efficient drainage for surface and storm water, and a ground moisture barrier where there is an enclosed subfloor.

Adequate insulation and heating matter too, because cold surfaces are where condensation forms.

The tenant must keep the premises reasonably clean and tidy (s40(1)(c)) and notify the landlord as soon as possible after discovering damage or the need for repairs (s40(1)(d)).

So the honest position is: mould is not automatically anybody's fault, and finding out whose it is falls to the landlord, because the landlord is the one who can inspect the building.

The first 48 hours

1. Acknowledge in writing, the same day. Most mould findings against landlords turn on silence, not on the mould. A dated reply saying you have received it and when you will look is the single highest-value thing you do.

2. Ask for photographs and specifics. Which rooms, which surfaces, how long, is it returning after cleaning, is there a smell, any visible water staining. Ask whether anything changed recently: a new tenant, a broken fan, a blocked gutter.

3. Arrange to inspect. Entry to investigate and carry out repairs is 24 hours' notice stating the reason, between 8am and 7pm (s48(2)(d)). If you fold it into a routine inspection instead, that is a 48-hour notice and it cannot happen more than once every four weeks, so it is usually slower.

4. Look for a cause, not just the mould. Check the extractor fans actually vent outside rather than into the ceiling space, that gutters and downpipes are clear, that there is no subfloor pooling, that the ground moisture barrier is intact, and whether the affected wall is an uninsulated external one.

5. Fix the cause and record it. Cleaning mould without addressing why it is there guarantees a repeat report in six weeks, and a repeat report is what makes a Tribunal treat the first one as ignored.

If you are the tenant

Report it in writing the day you see it, even if you also phone, because s40(1)(d) turns on when you discovered it. Photograph it with something for scale and keep the originals with their dates. Keep paying rent: withholding creates a separate breach that will be used against you. Air the property and use the extractor fans, both because it helps and because you will be asked.

If nothing happens, the ladder is a 14-day notice to remedy, then free mediation through Tenancy Services, then a Tribunal application.

Why these cases are really decided

Adjudicators rarely get expert evidence on mould causation. What they get is a timeline. Whoever can show dated photographs, a dated report, a dated response and a dated repair tends to win, because that is the only thing in the file that is not contested recollection.

That cuts both ways. A landlord with entry notices, inspection reports and a tradie invoice can show the building was maintained. A tenant with a dated report and no reply for five weeks can show it was not.

Keeping the record without effort

This is exactly what the maintenance workflow in RentManager is for. The tenant raises the report from their portal with photos attached, so it is timestamped on arrival rather than living in someone's phone. You approve and assign a tradie, and the job carries the photos and the address. Inspection reports with their own photos sit against the same property, so "what did the bathroom look like in March" has an answer.

Healthy homes compliance is tracked per property against each standard with its deadlines, so ventilation and drainage are recorded facts rather than something you hope was done before you bought the place.

Related reading: who is responsible for mould, who pays for rental repairs, what counts as urgent, and entry notice for repairs. Find a trade in the tradie directory, or browse everything in the Landlord Hub.

Common questions

Is mould in a rental the landlord's responsibility in NZ?

It depends on the cause. If mould results from a building fault such as a leak, failed drainage or inadequate ventilation, it is the landlord's to fix under the repair duty and the healthy homes standards. If it results from how the property is being lived in, such as unvented indoor drying with windows permanently closed, responsibility can sit with the tenant. Investigating which it is falls to the landlord.

Do the healthy homes standards cover mould directly?

Not by naming mould. They address the conditions that cause it: the ventilation standard requires openable windows and extractor fans in kitchens and bathrooms, and the moisture ingress and drainage standard requires efficient drainage and, for homes with an enclosed subfloor, a ground moisture barrier.

Can a tenant end a tenancy because of mould?

Not unilaterally on the basis of mould alone. A tenant can apply to the Tenancy Tribunal, which can order work, award compensation, reduce rent or in serious cases terminate the tenancy where the premises are uninhabitable. The route is a 14-day notice to remedy, then mediation, then the Tribunal.

General information about the Residential Tenancies Act 1986 and the healthy homes standards, current as at August 2026. Not legal or health advice.