Researchers Unveil Free Granny Flat Plans to Aid Families

Homeowners in New Zealand can now access architectural plans for granny flats, thanks to a new initiative from researchers at Auckland University. The plans are free to download and align with the Building and Construction (Small Stand-alone Dwellings) Amendment Act 2025, which came into effect on January 15, 2026. Funded by Branz, New Zealand’s independent building research organization, this project aims to support families seeking intergenerational living arrangements.

Led by Professor Anthony Hōete, who is of Ngāti Awa descent, the initiative has received $220,000 in funding for an 18-month research project. Hōete emphasizes that the open-source plans, designed for buildings up to 70 square metres, will provide valuable housing solutions. “They could be for kaumātua [respected elders], transitional housing, or even extra rooms for children,” he explains.

As part of the initial research phase, the team will assess 1,000 properties to gather insights on living conditions and property layouts. Using this data, they plan to create six different designs, complete with full sets of drawings, documentation, and specifications. Homeowners will be able to download these resources at no cost.

In collaboration with Context Architects, known for their work in affordable housing for Kāinga Ora, the project focuses on creating aesthetically pleasing and sustainable homes. The estimated construction cost is between $3,500 and $4,000 per square metre, totaling less than $300,000 for a complete granny flat.

Some designs will prioritize universal accessibility, ensuring homes are suitable for people with disabilities, including seniors. Hōete expresses enthusiasm for the project, noting its potential to empower individuals during challenging economic times. “This is going to give people tangible options,” he states. “They can choose from a suite of schemes, find a builder, and implement them.”

The granny flat initiative is part of a broader funding round where $11.5 million will be allocated to 22 projects aimed at enhancing building quality and sustainability in New Zealand. This funding comes from the Building Research Levy of 0.1%, which is applied to all building consents over $20,000. A group of independent experts evaluates and selects projects that focus on practical solutions to reduce costs and improve housing resilience.

Other notable projects funded in this round include “Whakamaru i te Rangatahi,” aimed at navigating housing solutions for rangatahi and whānau, and “Architecture for All,” which focuses on building equity through artificial intelligence and family-centered design.

The granny flat legislation itself, passed by Parliament in October 2025, simplifies the process for homeowners. It allows the construction of self-contained dwellings without the need for standard building consent, provided they meet specific criteria. The legislation is expected to facilitate the construction of around 13,000 granny flats over the next decade, contributing to the housing supply crisis in New Zealand.

In summary, this initiative not only reflects a significant investment in affordable housing solutions but also underscores a commitment to fostering intergenerational living arrangements in New Zealand. As families face ongoing economic challenges, the availability of these resources may provide much-needed relief and flexibility in housing options.