The number of landlords who will be stung by fines for not properly insulating their rental homes appears to be very low, according to a group representing property owners and investors.
But the Green Party says there are still likely "tens of thousands" of rental properties not properly insulated.
A report from the New Zealand Property Investors' Federation (NZPIF) showed that 96 per cent of the 1325 members the group surveyed have met the insulation deadline, which comes into effect tomorrow.
From July 1, tenants can seek up to $4000 in compensation from their landlords if their homes are not properly insulated.
"I am thrilled that our membership has an almost 100 per cent compliance rate with the insulation regulations," NZPIF's Executive Officer Andrew King said.
He urged all landlords in New Zealand to insulate their rental properties immediately if they have not already done so.
"As landlords, we have a responsibility to provide safe, warm and dry properties to Kiwi renters."
Despite this, Greens Co-Leader Marama Davidson has speculated that tens of thousands of rental properties are likely to be in breach of the rules.
She has urged all renters to check that they have ceiling and underfloor insulation as required by law.
"This is about protecting our community from winter illnesses, lowering our power bills and energy use, and making homes more liveable," she said.
"New Zealand's housing stock is in poor condition and we should never have allowed homes to be rented that could make children and the elderly ill over winter."
The new rules are the first step in wider changes under the Healthy Homes Standards that will come into effect in 2021.
When making the announcement in February, then Housing Minister Phil Twyford said the new requirements would mean rental homes across the country were warmer and drier.
"Nearly 600,000 households rent in New Zealand, and our rental stock is of poorer quality than owner-occupied homes. It's estimated about 200,000 families live in rental homes that do not have ceiling or underfloor insulation.
Landlords are required to install ceiling and underfloor insulation wherever possible. Wall insulation, however, is not compulsory.
According to information on the Ministry of Business, Innovation and Employment (MBIE) website, any landlords who still don't comply after paying the penalty, may face "further action".
Landlords who have installed new insulation since 2016 should already meet the 2008 Building Code and, as such, won't need to do install more insulation.
• July 1, 2021 – Private landlords must ensure that their rental properties comply with the healthy home standards within 90 days of any new tenancy.
• July 1, 2021 – All boardinghouses must comply with the healthy home standards.
• July 1, 2023 – All Housing New Zealand houses and registered Community Housing Providers houses must comply with the healthy home standards.
• July 1, 2024 – All rental homes must comply with the healthy home standards.