More than 90 per cent of New Zealand rental homes inspected in a pilot warrant of fitness test failed to pass.
The trial, which assessed 144 properties across Auckland, Tauranga, Wellington, Christchurch and Dunedin, found the vast majority (94 per cent) failed on at least one of the 31 criteria on the checklist.
Carried out by home assessment experts, the inspections looked at weathertightness, insulation and ventilation, lighting, heating, condition of appliances and general building safety.
The top five areas that rental homes failed on were water temperature, lack of smoke alarms in bedrooms, lack of code-compliant handrails and balustrades, lack of a fixed form of heating, and security.
However, around 36 per cent of the homes inspected would require only a few minor fixes, estimated to cost between $50 - $150, to pass the WOF, the trial's organisers said.
Some changes were as minor as inserting batteries in smoke alarms or adjusting water temperature.
The trial WOF comes amid calls for the introduction of a standardised criteria for rental properties to meet.
It tested a range of areas that could potentially be included in a housing WOF, aiming to identify aspects such as average assessment times and how to best communicate results to landlords and tenants.
Top five failed criteria: