Complex Home Modifications
Explained
Not all home modifications are created equal.
When the scale, cost, or risk of a project increases, it crosses into what the NDIS defines as a complex home modification.
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These types of modifications come with stricter requirements — including the need for a licensed Project Manager and a detailed Building Construction Process (BCP) report — to ensure participant safety, legal compliance, and correct use of NDIS funding.
What Makes a Modification “Complex”?
According to the NDIS Operational Guidelines, a home modification is considered complex when it involves one or more of the following:
1
Structural changes to the building, such as removing or relocating walls, doorways, or key infrastructure.
2
Works exceeding $20,000 in total cost, which automatically triggers additional regulatory oversight.
3
Changes to plumbing, electrical, or waterproofed areas, like bathrooms, kitchens, or laundry spaces.
4
Modifications that require building approval under state or territory legislation.
5
Coordination of multiple trades or technical professionals, such as builders, plumbers, electricians, engineers, and certifiers.
In short, a complex modification is any project that introduces higher risks, impacts critical infrastructure, or requires expert management to meet legal and building standards.
​Legal & Licensing Requirements
If your home modification is complex, the NDIS expects strict adherence to compliance standards — and additional layers of professional oversight. Specifically the NDIS requires:
A Building Construction Process (BCP) Report
This is a technical report that outlines:
The scope of works
Reasonable and necessary justifications
Risk assessments
Proposed materials and layouts
Estimated costs and builder quotes
BCPs are used by the NDIA to determine if funding will be approved — so accuracy and clarity are critical.
A Licensed Building Works Project Manager. When projects exceed $30,000 or are structurally complex, a licensed Project Manager is expected to:
Manage the full project lifecycle
Oversee builder compliance
Coordinate site inspections and milestones
Ensure the works meet building codes, Australian standards, and state legislation
This person must hold the appropriate builder’s license for your state or territory. Without this, the project may become non-compliant — and participants, OTs, and providers could be exposed to risk.
What Happens If You Don't Use a Licensed Project Manager?
Engaging an unqualified or unlicensed manager can result in:
Non-compliance with building authority regulations
Delays in funding or payment claims
Incomplete or unsafe works
Liability falling on the OT, provider, or participant
Legal action or penalties for working outside of licensing laws