There has been a major step forward in the rollout of the Nationwide House Energy Rating Scheme (NatHERS) for existing homes, with Design Matters National (DMN) announced today (19 February 2026) as the successful and exclusive provider of accreditation services for NatHERS for existing homes assessors.
Australian governments are working together to deliver energy ratings for existing homes. To do this the Nationwide House Energy Rating Scheme (NatHERS) is being expanded. Previously, NatHERS has only been available for rating new homes and major renovations.
DMN already supports Energy Efficiency Assessors as one of three NatHERS for New Homes Assessor Accrediting Organisations. This new appointment extends that experience into the existing homes space, ensuring consistent, high-quality accreditation and oversight for assessors working on Australia’s existing housing stock.
From April 2026, DMN will be receiving applications for accreditation and overseeing the performance of accredited NatHERS for existing homes assessors. This appointment comes ahead of Stage 2 of the NatHERS expansion, planned for mid 2026, when training and accreditation will be made available to all interested assessors. This will help provide more assessments to more households, supporting better performing, more comfortable homes across Australia.
Stage 1 of the NatHERS expansion, which is currently underway, commenced in July 2025 with a 12 month scaleup period to refine processes, tools, and training in preparation for the broader rollout.
“Design Matters National is the peak body working to represent, and enhance the profile and performance of Building Designers, Energy Efficiency Assessors, and other built environment professionals in Australia,” she said.
DMN CEO Danielle Johnston said the new appointment aligned closely with the organisation’s purpose and long-term commitment to energy efficiency.
“Our appointment as the accreditation provider for NatHERS for Existing Homes Assessors recognises the depth of expertise within our membership and our strong track record supporting NatHERS Assessors for New Homes. We warmly thank the Department of Climate Change, Environment, Energy and Water (DCCEEW) and the NatHERS Administrator for this appointment and look forward to working together to help deliver more, and better, assessments for Australian households.”
Design Matters National’s Senior Manager, Home Energy Efficiency & Sustainability, Vicki Marshall, said the new role would help support a high standard of practice across the emerging existing homes market.
“Existing homes are critical to Australia’s energy and emissions future,” she said.
“By accrediting NatHERS assessors for existing homes, DMN will help ensure that homeowners receive high-quality, consistent advice on how to improve the comfort and performance of their homes. We will work closely with NatHERS to support assessors with clear guidance, professional development and robust quality assurance.”
Design Matters National’s Purpose
This appointment reflects DMN’s broader statement of purpose. Design Matters National:
- provides members with information, collaboration and educational opportunities to promote excellence in their design work and business practices
- partners with industry leaders, and advocates to government and statutory bodies about things that matter to DMN members
- believes sustainability, quality, and innovation are essential to advance a better designed built environment in future Australia
Further details about accreditation requirements, training and timelines for NatHERS for existing homes assessors will be shared with DMN members and the wider industry as Stage 2 of the NatHERS expansion approaches.
For more information about DMN’s role in NatHERS and membership options, visit: