The three levels of home modification
The NDIA groups home modifications by cost and complexity, and the assessment you need depends on the level:
- Category A minor home modifications: under $10,000, with no structural change, such as grab rails, handheld showers or small ramps
- Category B minor home modifications: $10,000 to $20,000, or any minor works to a bathroom floor, still without structural change
- Complex home modifications: structural or custom works, usually over $20,000, often needing building approval, such as a full bathroom redesign or widening doorways
Who can do the assessment
For Category A works, an occupational therapist can complete the assessment. For Category B and complex works, the NDIA expects a home modification assessor: a registered OT with postgraduate training or education in assessing, specifying and implementing complex home modifications.
Ask any assessor how many similar modifications they have specified. Experience matters, especially for bathrooms and access to the home.
What the assessment covers
- How you move around and use each relevant room now, including transfers, showering and getting in and out
- Your goals, your support needs and who helps you
- Measurements of the space and your equipment, such as a wheelchair or commode
- Options considered, including assistive technology instead of building work
- A specific scope of works, with drawings or specifications for larger jobs
- Why the works are reasonable and necessary and value for money
Quotes, builders and project managers
For complex works the NDIA can fund a building works project manager, who must be independent of the builders quoting on the job. It can also fund a building construction practitioner to work with you and your assessor on the scope of works before quotes are sought.
Builder quotes should match the assessor's scope exactly. Mismatched quotes are a common reason for delays.
Renting or not your home?
If you rent or live in someone else's home, you need the owner's written permission before works start. Social housing tenants should also talk to their housing provider, who may be responsible for some modifications. The NDIA also considers whether moving to a more suitable home would be a better option than major works.
Funding and the 2026 changes
The OT's assessment time usually comes from your Capacity Building budget, typically improved daily living skills, at up to the NDIS price limit of $193.99 an hour for occupational therapy in 2026/27 in most of Australia. The works themselves are funded from your Capital budget.
Home modifications are protected from the October 2026 funding reset, so the change to improved daily living skills budgets does not touch the works funding itself.
For OTs and builders
Use the NDIA's complex home modifications assessment template for complex works. Show the cheaper options you considered, include photos and measurements, and make sure the scope is specific enough for builders to quote like for like.