SDA Housing Development in Australia: A Developer's Guide

Specialist Disability Accommodation, usually shortened to SDA, is purpose-built housing for people with extreme functional impairment or very high support needs, funded through the National Disability Insurance Scheme (NDIS). For a developer, the important thing is not the design brief. It is that SDA runs on a completely different revenue mechanism to anything else you build. There is no market rent and no purchaser. The dwelling earns a payment set by the National Disability Insurance Agency (NDIA), and it earns nothing at all until three separate things are true at once: the entity being paid is a registered NDIS provider, the dwelling is enrolled with the agency, and an eligible participant actually lives in it.

Before considering an SDA housing development, you’ll need professional advice from a lawyer and an accountant, and a town planner in the jurisdiction you are building in. The obligations sit on you. Enrolment conditions bind the provider and can be cancelled. Land tax and GST treatment differ by state and by structure. Residency arrangements in some states are governed by their own part of the tenancy legislation with its own notice rules. If the enrolment does not come through, or comes through for a different design category than you built to, the loss lands on your balance sheet. This guide is written to make that conversation with your advisers sharper. It does not replace it.

Every figure, threshold and rule below was current at the date of writing and they change. The SDA price limits are reissued each financial year, the design standard is under review, and two of the state provisions covered here have live expiry dates. Each point links to the primary source, and that source is where to confirm the current position before you commit.

What is SDA housing, and what is a developer actually building?

SDA is defined in the National Disability Insurance Scheme (Specialist Disability Accommodation) Rules 2020 as accommodation for a person who requires specialist housing solutions, including to assist with the delivery of supports that cater for the person’s extreme functional impairment or very high support needs. Critically, the same definition says SDA “does not include supports delivered to the person while the person is living in the accommodation”.

That split matters more than it looks. SDA is the bricks. The care delivered inside is a separate NDIS support, usually supported independent living, bought from a separate provider and funded separately. A developer building SDA is building a physical asset that generates a housing payment. A developer who assumes the care revenue comes with the building has misread the scheme.

The four SDA building types

Schedule 1 of the SDA Rules sets out four building types and their Building Code of Australia classification:

The Rules are specific about the boundaries. A self-contained dwelling separated from other dwellings by walls alone is not an apartment; it is likely a villa, duplex or townhouse. A villa, duplex or townhouse may be an ancillary dwelling on the same parcel as another dwelling, such as a fully self-contained granny flat.

The five design categories, four of which can be funded

Schedule 2 of the Rules sets out five design categories:

• Basic: housing without specialist design features but with a location or other features that cater for the needs of people with disability.
• Improved liveability: designed to improve liveability by incorporating a reasonable level of physical access and enhanced provision for people with sensory, intellectual or cognitive impairment.
• Fully accessible: designed to incorporate a high level of physical access provision for people with significant physical impairment.
• Robust: designed to incorporate a high level of physical access provision and be very resilient, while reducing the likelihood of reactive maintenance and reducing risk to residents and the community.
• High physical support: designed to incorporate a high level of physical access provision for people with significant physical impairment and requiring very high levels of support.

Section 17(2) of the Rules says the CEO of the National Disability Insurance Agency (NDIA), referred to throughout the Rules simply as the CEO, “must not determine for an eligible participant the SDA design category of basic”. In practical terms, basic is a legacy category, not something you build to. New development targets one of the other four.

New build, existing stock or legacy stock

Section 8 of the Rules defines a new build as a dwelling where a certificate of occupancy or equivalent was first issued on or after 1 April 2016 (or issued after that date following renovations or refurbishments that brought the dwelling up to the minimum design requirements for a category other than basic), enrolled to house five or fewer long-term residents excluding support staff, where the shared areas and at least one bedroom and one bathroom satisfy the minimum design requirements for a category other than basic.

Existing stock (section 6) and legacy stock (section 7) cover older dwellings that are not new builds and that housed a resident with extreme functional impairment or very high support needs receiving government supported accommodation payments between 1 July 2013 and 1 December 2016. Existing stock houses five or fewer long-term residents; legacy stock houses more than five. Neither is a route into new development.

For a new project, only the new build definition matters, and the five-resident cap in section 8(b) is the one to note early. It is a design constraint, not an operational one.

Who gets paid for SDA, and why registration comes before the build

The SDA payment goes to an SDA provider, which the Rules define as a registered NDIS provider registered to provide SDA. Registration is not optional and it is not something to leave until the building is finished. The NDIS Quality and Safeguards Commission states plainly on its about registration page that you must be registered to provide SDA. Registration is generally granted for three years.

Two features of that process are worth building into your programme:

SDA sits in registration group 0131 and requires a certification audit, not a verification audit. The commission’s registration groups table lists registration group “0131 Specialist disability accommodation” against a certification audit. Where an application covers registration groups associated with both audit types, the certification audit applies to the whole application, and it is the more involved of the two.

You engage and pay the auditor. The commission’s apply for registration guidance sets out the sequence: worker screening, an online application including a self-assessment against the NDIS Practice Standards, then engaging an independent auditor from the commission’s approved list, then the auditor’s recommendation and the commission’s own suitability assessment of the provider and its key personnel. Applications must be completed within 60 days of starting or they are deleted. The commission does not publish a processing time, saying only that it depends on the size, scale and complexity of the organisation and its supports. Providing false or misleading information in an application contravenes section 73D of the National Disability Insurance Scheme Act 2013 and carries a civil penalty.

The owner and the provider do not have to be the same entity

Many SDA structures separate the property owner from the registered provider, and the Rules accommodate that with conditions. Section 25(4)(j) requires that where the dwelling is owned by someone other than the applicant, the owner has agreed in writing both that the applicant can enrol the dwelling and that the owner will not separately enrol it.

The practical consequence for a developer selling a completed SDA dwelling: the buyer’s ability to earn on it depends on a registered provider being willing to enrol it, and on that written owner consent existing. That is a contractual matter to sort out before settlement, not after.

Which participants can live there, and why that shapes the product

You are not building for a market. You are building for a set of participants whose plans specify a particular building type, design category and location. Get the match wrong and the dwelling can be enrolled and still sit empty.

Under section 11 of the Rules, a participant is eligible for SDA if the CEO is satisfied they have an extreme functional impairment (section 12) or very high support needs (section 13), and they meet the SDA needs requirement (section 14). Section 15 then requires the CEO to determine, for each eligible participant, the SDA building type, the SDA design category and the area in which the accommodation is to be located. Section 19 requires those determinations to be written into the participant’s plan along with the amount of support available.

The location determination is the one developers tend to underweight. Section 18(2) requires the area to be an Australian Bureau of Statistics Statistical Area Level 4, or part of one, or two or more of them. Those regions are large, typically covering a whole sector of a capital city or a substantial regional area, so demand is expressed at that geography rather than by suburb. A dwelling in the right region but in a location with poor transport or no nearby support workforce may satisfy the plan and still struggle to fill.

Section 16 lists the matters the CEO must weigh in setting the building type, and they are worth reading if you are choosing between an apartment and a house on a given site. They include the participant’s stated preference, whether the support model calls for immediately available or constant person-to-person support, whether the building type helps social and economic participation, and whether it represents value for money relative to alternatives.

Before committing to a design category, the sensible order is to look at published demand for that Statistical Area Level 4 region and then design, rather than the reverse. The agency publishes SDA demand data and updates it periodically, with one caveat worth carrying into your own numbers: the agency’s data page records an SDA Data Project run across 2024 to 2025 to review the accessibility and reliability of that data, and says “the improvements needed to boost SDA data quality are part of a longer-term initiative”.

How does SDA design standard certification work, and when does it happen?

Certification happens twice, and the first one happens before you start building. The NDIA’s SDA design standards page states that dwellings are certified at the design stage before construction commences, and then certified again by an accredited SDA assessor at final as-built stage. The standard was published in October 2019 and applies to all new build SDA from 1 July 2021. It does not apply to dwellings seeking enrolment as existing or legacy stock.

The assessor must be genuinely independent

The certification “must be signed by an accredited third-party SDA assessor who is not an employee, associate or otherwise contracted by the provider, developer or owner”. An accredited SDA assessor is the only person who can issue certification, and the agency does not engage assessors itself. Assessors cannot certify projects they designed, built, or assessed as building surveyor or certifier.

Only four professions can become assessors: architects, access consultants, occupational therapists, and building surveyors or certifiers. Each must additionally hold a Certificate IV in Access Consulting or a Diploma of Access Consulting. Assessors must carry professional indemnity insurance of $5,000,000 and public liability insurance of $10,000,000. That insurance level tells you something about how the agency views the risk in the certification itself.

For a developer, the sequencing point is simple: the access consultant or assessor engaged for design stage certification cannot be the same person who designed the dwelling, so you may be carrying two accessibility-literate consultants on the project rather than one.

The design stage register publishes your pipeline

When an assessor lodges design stage certification, the agency records the project on a design stage register and then releases data from it “to inform the market of the pipeline of work under development, noting that commercial in confidence or identifying information is protected”. Your competitors get a de-identified view of supply coming into a region, and so do you, which is useful when testing whether a design category is about to be oversupplied. The agency is equally explicit that being on the register does not mean the dwelling will be enrolled, or enrolled as the same building type and design category shown there.

The design standard is currently under review

The NDIA announced in September 2025 that it had partnered with KPMG Australia to review the SDA Design Standard, so that “new build SDA design requirements stay aligned with industry standards”. Consultation ran through late 2025 and has closed. A revised edition has not been published at the date of writing, and transitional arrangements are not known. If you are designing now for a build completing in two years, that is a live risk to price into your programme and a question worth putting to your access consultant.

What does enrolment involve, and why certification does not guarantee it?

This is the single most expensive misunderstanding in SDA development. The agency says it directly on its design standards page:

SDA Design Standard certification doesn’t mean that the dwelling will be enrolled as SDA… The NDIA won’t enrol a dwelling if the provider and the dwelling don’t meet all of the requirements for enrolment under the SDA Rules at the time of the decision. This is regardless of the Design Standard certification by the accredited SDA assessor, or previous assessment, feedback or certification provided by the NDIA or any other party.

Design stage certification tells you the drawings comply. As-built certification tells you the building complies. Neither is a commitment that the agency will enrol.

You cannot apply until the building is finished

The agency’s guidance on enrolling a home as SDA states: “You can only apply to enrol a home as SDA if it’s built and complete. A home is complete when a certificate of occupancy, completion or equivalent is issued.”

That single sentence sets the shape of your funding profile. The enrolment application starts after practical completion, and tenanting starts after enrolment. There is no way to bring the first SDA payment forward past the certificate of occupancy, so the holding cost between completion and first payment is real and it is yours.

What the application requires

The agency’s published document list includes proof of ownership; permission to enrol where the owner and SDA provider differ; the certificate of occupancy or equivalent; refurbishment costs where relevant; and SDA design standard final as-built certification documents. Applications are lodged through the my NDIS provider portal, and the agency states: “We aim to let you know if your application is approved within 28 days.”

Section 25(4) of the Rules also requires the applicant to certify a list of matters, several of which have real commercial consequences:

• The dwelling meets all relevant building codes, standards and laws that apply to it.
• The NDIS has not funded or provided complex home modifications for the dwelling within the past ten years, or other home modifications within the past five years (both measured from 1 December 2016 onwards).
• The Commonwealth, or a state or territory, does not provide funding in respect of the dwelling under a scheme unrelated to disability accommodation.
• The applicant has suitable capacity and experience to provide SDA at the dwelling.
• A density restriction applying to the parcel would not be exceeded if the dwelling is enrolled.

That third one catches developers who have layered SDA on top of another government housing programme. If the site or dwelling receives unrelated Commonwealth, state or territory funding, the certification cannot be given, so it is worth checking before accepting any grant or concession tied to the dwelling. A decision not to enrol is reviewable under section 26(3).

What does the density restriction do to your site?

Section 31 of the Rules caps how much SDA can sit on one parcel of land, and it is the provision most likely to kill a scheme that otherwise stacks up.

The restriction applies where a parcel has two or more dwellings and at least one of them is a new build or existing stock. Where it applies, the total number of eligible participants who can receive SDA funding across all dwellings on the parcel must not exceed:

• Where one of the dwellings on the parcel is enrolled to house three or more residents: the greater of 10 eligible participants, or 10 per cent of the total number of residents capable of residing on the parcel assuming one resident per bedroom.
• Where all enrolled dwellings on the parcel house no more than two residents and form part of an intentional community: the greater of 15 eligible participants, or 25 per cent of the total residents on the same one-per-bedroom assumption.
• Where all enrolled dwellings house no more than two residents and are not part of an intentional community: the greater of 15 eligible participants, or 15 per cent.

An intentional community is defined narrowly in section 31(3). It must be controlled by its members rather than a single entity such as a support provider, must have an explicit agreement to live by shared common values including mutual support, and must include general market housing rather than being solely designed to provide supported accommodation services.

The design consequence is direct. On a 60-apartment building on a single strata parcel, the 10 per cent test would generally cap funded participants well below what a developer targeting SDA yield might assume. Integration into general-market buildings is the model the restriction encourages, and concentration is what it prevents.

”Parcel of land” is defined differently in each state and territory

Section 31(4) sets out what counts as a parcel, jurisdiction by jurisdiction. In every case the test follows the titling instrument: the strata, community title or unit title scheme where one exists, and otherwise the folio, certificate of title, allotment or lot.

Because the parcel definition follows the titling instrument, how you subdivide can change how many participants the parcel can carry. That is a conversation to have with your surveyor and lawyer at concept stage, not after the plan of subdivision is registered.

How is SDA revenue actually structured?

There are two income streams and they behave differently.

The SDA payment. The NDIA publishes SDA pricing arrangements that set out what it considers “the appropriate and reasonable maximum prices for SDA supports”. The arrangements are reissued each financial year and are accompanied by an SDA price calculator, which the agency says “can help you understand the expected annual income for an enrolled SDA home”. Because the limits change annually, no guide should quote them; the calculator for the current year is the only figure worth modelling on.

The price for a given dwelling is built up from the design category, the building type, the number of residents it is enrolled for, and the location. The published arrangements also provide for a room used for onsite overnight assistance (not a bedroom, and paid only where the room is actually used by support staff providing overnight support), an additional breakout room in robust design dwellings, and a fire sprinkler allowance. Those three are physical rooms and systems you either build or you do not, and each changes the price the dwelling can attract, so they belong in the design brief rather than in a later value-management exercise.

The reasonable rent contribution. Participants also pay rent directly to the provider, and the agency draws the line clearly on its investment in SDA page: “There is a difference between rental payments and payments for SDA… Certain day-to-day living costs, including rent, are not a NDIS support that can be funded through the NDIS.” The same page states that the rent charged “must not exceed the maximum reasonable rent contribution (MRRC) published in the NDIS Specialist Disability Accommodation Pricing Arrangements”. That maximum is published, it moves, and it is not a market rent.

Charging above the cap requires a valuer’s certificate

Section 29(1)(g) of the Rules treats a proposal to charge rent above the sum of the SDA payment and the reasonable rent contribution as a notifiable event. Section 29(2) gives the provider five business days to notify the CEO. Section 29(3) then requires the notice to be accompanied by “a certificate from a qualified property valuer stating that the rent to be charged is fair and reasonable”.

If your feasibility assumes revenue above the published limits, that is the mechanism you are relying on, and it is not a formality.

Pricing governance is changing

The NDIA’s page on securing the NDIS for future generations records that Parliament passed the amending Bill on 19 August 2026 and the Governor-General signed the new laws on 20 August. Among the changes: “The Minister for Disability and the NDIS will have the power to make a pricing determination for NDIS supports… This will be done through the existing Annual Pricing Review process. There are no immediate changes to NDIS pricing.”

For a developer underwriting a twenty-year hold, the point is not the current price. It is that the body setting it has changed. A long-dated feasibility built on a flat real SDA price is making an assumption about that process, and the assumption should be stated rather than buried.

What happens to income when a resident leaves?

Vacancy in SDA does not behave like vacancy in a rental block, because the funding follows the participant rather than the dwelling.

Section 24(1) of the Rules sets the conditions for SDA to be funded at all: the accommodation must be provided by an SDA provider at an enrolled dwelling, the eligible participant must reside there, and they must have a private bedroom meeting the minimum design requirements for a design category specified in their plan, occupied only by them unless they freely choose otherwise, plus access to a compliant bathroom.

Section 32 then gives a limited grace period. Where a dwelling is enrolled to house two to five residents and a participant dies, gives notice they will vacate, or is given notice to vacate because of behaviour representing a risk, and the vacancy is available for another person and the CEO has been notified, the participant is taken to continue residing there until the earlier of:

• the vacancy being filled;
• 60 days passing, where the dwelling is enrolled to house two or three residents; or
• 90 days passing, where the dwelling is enrolled to house four or five residents.

Read that closely. The grace period only applies to dwellings enrolled for two to five residents. A single-resident apartment gets no deemed-residence period at all. If you are choosing between an apartment product and a small group product on the same site, the vacancy exposure is materially different, and that difference belongs in the development cashflow model rather than in a footnote.

The notification obligations run alongside. Section 29(1)(e) and (f) require the provider to notify the CEO within five business days where a participant has given notice to terminate their occupancy or been given notice to vacate, and where a vacancy arises that is available to be filled.

What ongoing conditions attach to an enrolled dwelling?

Enrolment is not permanent, and the conditions are worth knowing whether you intend to hold the asset or sell it to someone who will.

• Section 28 requires the provider to keep each enrolled dwelling in a good state of repair and appropriately maintained. On a robust or high physical support dwelling, that is a heavier obligation than an equivalent market rental, and the sinking fund assumption should reflect it.
• Section 29 requires notification within five business days of a change in design category or building type, the dwelling becoming unsuitable, an intention to cancel enrolment, a participant giving or receiving a notice to vacate, a vacancy becoming available, and a proposal to charge rent above the cap.
• Section 30 allows the CEO to require recertification at any time, by an independent person the CEO specifies, confirming the information given at enrolment still applies.
• Section 27 allows the CEO to cancel enrolment where a condition is not being complied with, after a notice period of no less than 14 days.
• Section 37 prohibits a provider from restricting other NDIS providers from accessing the dwelling to deliver support. Building security, key management and access control need to be designed around that obligation rather than against it.
• Section 38 caps resident numbers at the number the dwelling is enrolled for, and section 39 makes contravention of these requirements a prescribed circumstance for revoking the provider’s registration entirely.

The asset-level risk to price is that enrolment is a condition-bearing status that can be cancelled, and cancellation takes the revenue with it.

What planning pathway applies in each state and territory?

There is no national planning treatment of SDA. Each jurisdiction slots it into an existing land use definition, and the fit is imperfect in most of them.

New South Wales

SDA is dealt with through the group homes provisions in Chapter 3, Part 2 of State Environmental Planning Policy (Housing) 2021. The NSW Department of Planning, Housing and Infrastructure sets out four approval pathways for group homes:

• Development without consent, in a prescribed zone, undertaken by a public authority, with up to 10 bedrooms.
• Exempt development, covering the use of an existing lawfully approved dwelling as a group home for a single household under a tenancy agreement with a relevant authority, and out-of-home care uses with no more than five bedrooms.
• Complying development, covering the development of a new group home with up to 10 bedrooms complying with the standards in Schedule 2 of the Housing State Environmental Planning Policy (SEPP) and specified clauses of the Codes SEPP, and change of use of an existing lawfully approved Class 1a building to a group home with up to 10 bedrooms.
• A standard development application.

The department states that where a proposal meets all the complying development requirements, “an application may be determined within 20 days by a local council or accredited certifier”. Group homes are permitted in R1, R2, R3 and R4 residential zones, B4 Mixed Use, SP1 Special Activities, SP2 Infrastructure, and any other zone where dwelling houses or multi dwelling housing are permitted.

A September 2025 reform modernised the definitions “for permanent and temporary group homes to reflect contemporary design models, including ‘core and cluster’”, and removed references to “a dwelling” and occupation by “a single household”. Older advice referring to “transitional group homes” and single-household occupation predates that change. The complying development pathway with a 20-day determination is the biggest planning advantage available to SDA anywhere in the country, and worth testing early against the Schedule 2 standards rather than assuming. For the wider NSW picture, see the NSW housing reforms guide.

Victoria

Victoria handles SDA through the community care accommodation provisions of the Victoria Planning Provisions rather than through an SDA-specific land use term. Those provisions were amended in 2022 to deal expressly with proposals funded through the NDIS, and they operate as a particular provision that can change both whether a permit is required and whether public notice applies.

The thresholds, the site area tests and the notice exemptions all sit in the current version of the provision as it appears in the relevant council’s planning scheme, and they are the kind of detail that moves. This guide deliberately does not restate them. The useful question for your town planner is a narrow one: does the community care accommodation provision apply to this dwelling on this site, does it exempt the application from notice and review, and what triggers a permit despite it.

Queensland

Queensland has no SDA land use term. SDA is assessed against the existing definitions in the Planning Regulation 2017, most commonly the “community residence” definition, which carries a resident cap that should be confirmed against the current regulation.

Separately, Queensland has a live and time-limited rooming accommodation reform that can be relevant depending on the model. The Queensland Department of State Development, Infrastructure and Planning states that the Planning Regulation “extends for 12 months, provisions which allow for small-scale rooming accommodation uses (max 5 bedrooms and 5 occupants) to not require planning approval (also called a material change of use approval) from the relevant Local Government in lower density residential zones, where prescribed requirements can be met. These provisions will now expire on 2 December 2026.”

The department also notes that “infrastructure charges will continue to apply to new developments… irrespective of whether the proposed rooming accommodation requires planning approval”, and that ongoing development rights are preserved for building works approved before 3 December 2025 provided the use commences within two years of completion. The instrument is the Planning Amendment Regulation 2025. The expiry date is the point to diarise: a scheme relying on that pathway needs to be through approval well before it lapses, or to have a fallback.

Western Australia, South Australia, Tasmania, the ACT and the Northern Territory

None of these five jurisdictions appears to have an SDA-specific planning provision. In Western Australia, SDA is generally assessed under the Residential Design Codes as a single house or grouped dwelling. In South Australia, the Planning and Design Code uses a supported accommodation land use class that SDA may fall within depending on the model. Tasmania, the ACT and the Northern Territory each assess SDA against their general residential definitions.

Where there is no bespoke pathway, the risk shifts from planning policy to neighbour objection and to whether the assessing officer reads the proposal as a dwelling house or as something more institutional. That is a matter of how the application is framed.

New Zealand

SDA is a creature of the Australian NDIS and has no New Zealand equivalent. None of the design categories, price limits, enrolment rules or state provisions in this guide apply there, and the SDA framework is not a useful reference point for supported housing across the Tasman.

What is the land tax and duty position, state by state?

This is where the largest single misunderstanding in the sector sits. Only one jurisdiction gives relief that turns on the dwelling being SDA-enrolled. Every other disability-related concession in the country attaches to something else, usually a person, a trust or a separate licensing regime.

Victoria: the only exemption tied to SDA enrolment

The Victorian State Revenue Office states, in its land tax exemptions guidance, that land is exempt from land tax if it is “occupied or currently available for occupation as a residential service for people with disabilities within the meaning of the Disability Act 2006, or as an SDA enrolled dwelling provided by an SDA provider within the meaning of the Residential Tenancies Act 1997”.

Three features to note. Partial use is apportioned, so where only part of the land is occupied or available for occupation, only that part is exempt. The evidence burden falls on the owner, who must show the dwelling is enrolled under the SDA Rules and that the provider is registered with the NDIS Quality and Safeguards Commission, plus, where the dwelling is leased, a copy of the lease between owner and SDA provider. And the exemption extends to land on which an SDA enrolled dwelling is under construction, but only for a limited number of tax years, so a slow build can run past it.

Victoria also has a separate person-based land tax exemption for a home owned by an immediate family member and used as the principal residence of an eligible person with a disability, and a separate land transfer duty exemption for a transfer to a qualifying person with a disability. Neither has anything to do with SDA enrolment, and conflating them is a common and expensive error.

New South Wales

Revenue NSW’s land tax exemptions do not include SDA. Boarding house, low-cost accommodation, retirement village and residential care exemptions exist, and each has its own test that an SDA dwelling will generally not satisfy simply by being SDA. Land tax should therefore be modelled as a full holding cost in a NSW SDA feasibility unless a specific exemption is confirmed on the facts. Land tax and the other recurring outgoings are covered in more detail in the guide to land holding costs.

Queensland

The Queensland Revenue Office lists a supported accommodation exemption, but it attaches to a different regime entirely: “A supported accommodation service is a residential service accredited at level 3 under the Residential Services (Accreditation) Act 2002.” SDA enrolment on its own does nothing for Queensland land tax. The office also notes that land tax exemptions are generally not automatic and must be applied for.

South Australia

RevenueSA’s exemption covers supported residential facilities licensed under the Supported Residential Facilities Act 1992, and residential aged care facilities. Licensing under that Act is a separate process from SDA enrolment and the two do not map onto each other.

Western Australia and Tasmania

Western Australia’s disability-related land tax exemptions are person-based, covering a private residence used by a person with disability as their primary residence where the property is owned by a parent, grandparent, brother or sister, and trust property used by a disabled beneficiary. Tasmania offers a special disability trust exemption. Neither turns on SDA enrolment.

Australian Capital Territory

The ACT has no SDA land tax exemption. It does have a Disability Duty Concession Scheme, and it is worth understanding precisely because it is often misread as an SDA incentive. It is available to ACT residents “who have qualified for an individual funding package under the National Disability Insurance Scheme (NDIS)” buying a home as their principal residence. From 1 July 2026 the property value limit was removed, so no conveyance duty is payable. But the participant “must acquire at least 51 per cent interest in the home”, must live in it as their principal place of residence continuously for at least a year, and cannot purchase with a non-individual such as a company.

That last condition rules the concession out for an SDA developer, an SDA provider or an investor. It helps a participant buying their own home. It does nothing for a build-to-hold SDA scheme.

Northern Territory

The Northern Territory has no land tax at all, so the question does not arise.

How does GST work on SDA?

SDA payments to a provider are GST-free where four conditions are met. The ATO’s guidance on the NDIS sets them out. A supply to an NDIS participant is GST-free if all of the following are true:

• the participant has an NDIS plan in effect under section 37 of the National Disability Insurance Scheme Act 2013;
• the supply is of reasonable and necessary supports specified in the statement of supports in the participant’s plan;
• there is a written agreement between the supplier and the participant or another person, identifying the participant and stating that the supply is of one or more of the reasonable and necessary supports specified under subsection 33(2) of that Act; and
• the supply is covered by one of the tables in the GST-free Supply (National Disability Insurance Scheme Supports) Determination 2021.

SDA is listed expressly as the first item of Table 1 of that determination, described as “specialist disability accommodation and accommodation or tenancy assistance”, with a note that the SDA Rules 2020 set out the requirements to be met. Table 1 items require no second determination.

Two practical points fall out of this. The written agreement condition is not satisfied by a generic tenancy document, though the ATO notes it “may be a single document or a combination of documents” and may be with a plan manager or the agency rather than the participant. The service agreement required by section 36 of the SDA Rules is doing double duty here. And the determination has a stated application period that has been amended more than once, so the current instrument on the Federal Register of Legislation is the place to confirm it, not the ATO page.

The GST treatment of the reasonable rent contribution charged to a resident is a separate question from the treatment of the SDA payment, and the general rules for residential premises apply to it. No public ATO ruling dealing specifically with SDA rent contributions surfaced in preparing this guide, so it goes on the list for your accountant rather than being answered here. The general position is covered in the GST and property development guide.

What tenancy or residency regime applies to SDA residents?

The answer varies by state, and Victoria is the outlier.

Victoria has a purpose-built regime. Part 12A of the Residential Tenancies Act 1997 (Vic) creates SDA residency agreements. The Victorian Government describes Part 12A as designed “to mirror many of the mainstream rights and duties of rental providers and renters under Part 2 of the Residential Tenancies Act 1997 (Vic) (RTA), with a range of additional protections for residents against eviction and exploitation”. Registered SDA providers must notify Consumer Affairs Victoria of all SDA residency agreements, and Community Visitors have the right to enter an SDA enrolled dwelling “at any time and without notice, and to exercise powers of inspection”. Three agreement types can apply to a household but only one at a time.

Consumer Affairs Victoria records changes that took effect on 1 July 2026: the rent in advance limit moved from 30 days to one month, providers must now give copies of certain notices to Consumer Affairs Victoria and to the NDIA, two new Director-approved notice forms were introduced, the Victorian Civil and Administrative Tribunal can make an exceptional agreement order where a resident is already occupying before an agreement is signed, and a new Schedule 4 deems certain SDA residency agreements valid and enforceable.

Queensland has no separate SDA regime. SDA falls into one of the two existing streams under the Residential Tenancies and Rooming Accommodation Act 2008: a general tenancy or rooming accommodation. The Residential Tenancies Authority publishes an SDA-specific rental application form, but a form is not a regime. The authority also flags that a resident’s impaired capacity may affect their ability to understand, negotiate and sign a rooming accommodation agreement, and that an agreement with special conditions may not be enforceable.

New South Wales has no SDA-specific part in the Residential Tenancies Act 2010. A separate occupancy regime exists under the Boarding Houses Act 2012 (NSW) for assisted boarding houses, defined as boarding premises accommodating two or more persons with additional needs for fee or reward, where residents sign an occupancy agreement rather than a residential tenancy agreement. How that legislation interacts with an SDA dwelling in NSW is a genuine legal question, and one to put to a NSW property lawyer rather than assume either way.

Across every jurisdiction, section 36 of the SDA Rules sits on top: a registered provider must not provide SDA to an eligible participant without a written service agreement setting out the rights and responsibilities of both parties and including the terms required by the addendum to the Terms of Business for Registered Providers.

What drives SDA build cost above a standard dwelling?

There is no published government cost benchmark for SDA construction, so any figure quoted anywhere should be treated as market commentary rather than fact. What can be said with confidence is where the cost sits, because it follows from the design categories themselves.

The main drivers, roughly in order of impact:

• Structural provision for ceiling hoists in high physical support dwellings, which affects the roof structure and ceiling framing over bedrooms and bathrooms, and is difficult to retrofit.
• Circulation and door widths, which increase gross floor area for the same number of bedrooms. This is the quiet one: you are paying for square metres that generate no additional revenue line, so cost per square metre understates the impact and cost per bedroom overstates the efficiency.
• Bathroom size and fit-out, particularly in fully accessible and high physical support dwellings.
• Impact-resistant and tamper-resistant construction in robust dwellings, plus a breakout room that occupies floor area.
• Services resilience, including backup power provision in high physical support dwellings, and fire safety systems.
• A room for onsite overnight assistance, which is not a bedroom and houses no funded participant, but attracts a separate amount when actually used by overnight support staff.
• Two rounds of certification plus an independent assessor who cannot be your designer.

The right way to size these is a cost plan from a quantity surveyor who has priced SDA before, tested against the specific design category rather than a generic accessible-housing rate. General cost benchmarking is covered in the guide to construction cost per square metre.

What does the cost stack look like on a four-bedroom high physical support house?

The figures below are illustrative only and are there to show how the pieces reconcile. Replace every input with your own quantity surveyor’s cost plan and your own quotes.

A four-bedroom high physical support house with one onsite overnight assistance room, on a serviced lot in an outer growth corridor:

Construction is $720,000 plus $144,000, or $864,000. Professional fees of $77,760 are 9 per cent of that figure and contingency of $43,200 is 5 per cent of it. Add land, statutory costs, site costs, finance and the enrolment allowance and the total is $1,659,960.

The revenue side cannot be filled in from a guide, because the price limits are reissued annually. The structure is:

(SDA price for the design category, building type, resident count and location, multiplied by the number of eligible participants actually residing) + (onsite overnight assistance amount, where the room is used) + (reasonable rent contributions, capped at the published maximum) − operating costs, land tax where applicable, insurance, maintenance and management

Run that against the current-year SDA price calculator published with the pricing arrangements, over the $1,659,960 cost base, and you have a yield you can defend.

A second scenario. Change one input: assume three of the four bedrooms are occupied by eligible participants for a full year rather than four. SDA payment revenue falls by roughly a quarter while the cost base is unchanged, and outside the deemed-residence window in section 32 there is no payment at all for the empty bedroom. Change a second input, and build the same accommodation as four single-resident apartments instead of one four-bedroom house: section 32’s deemed residence disappears entirely, because it only applies to dwellings enrolled for two to five residents. Same participants, same design category, materially different vacancy exposure.

Because the return depends on a long income stream rather than a sale, the metric that matters is a project internal rate of return over the hold rather than a development margin at completion. Depreciation also becomes part of the after-tax return, covered in the guide to Division 43 depreciation for build-to-hold developers.

What to ask your lawyer

• Who will hold the enrolment, what happens to it if I sell the dwelling, and what does the buyer actually acquire?
• If the owner and the SDA provider are different entities, what does the written owner consent under section 25(4)(j) need to say, and how do I stop the provider from walking away with the enrolment?
• Does this site or dwelling receive any Commonwealth, state or territory funding under a scheme unrelated to disability accommodation? If so, can the section 25(4)(g) certification be given at all?
• On my proposed subdivision or strata plan, what is the “parcel of land” for the purposes of section 31, and how many funded participants can that parcel carry?
• In this state, what residency or tenancy regime applies to residents, and what notice and termination rights does that give them? In New South Wales, how does the Boarding Houses Act 2012 interact with an SDA dwelling of this configuration?
• What happens contractually if enrolment is refused, or granted for a different design category or building type than the one certified?
• What are my exposures under sections 27 to 30 if enrolment is later cancelled for a maintenance or notification failure?

What to ask your accountant

• Is the reasonable rent contribution I charge residents an input taxed supply of residential premises, and if so, what does that do to my input tax credits on construction?
• Given SDA is a Table 1 item in the GST-free Supply (National Disability Insurance Scheme Supports) Determination 2021, what is the current application period of that instrument, and what is my position if it lapses without extension?
• Does the service agreement I am using satisfy the ATO’s written agreement condition for a GST-free NDIS supply?
• In this state, am I entitled to a land tax exemption, and on what basis? If we are relying on the Victorian SDA enrolment exemption, how long does the construction-period extension run and what happens if the build overruns it?
• How should this be structured for the hold, given the income is a government payment rather than market rent and there is no sale event to plan around?
• What is the depreciation position on the design-category uplift, the onsite overnight assistance room and the specialist fit-out?

What to ask your town planner

• Which land use definition does this dwelling fall under in this jurisdiction, and does that classification change with the number of residents?
• In New South Wales, can this be delivered as complying development under Schedule 2 of the Housing SEPP, and what would need to change in the design for it to qualify?
• In Victoria, does the community care accommodation provision apply on this site, does it exempt the application from notice and review, and what would still trigger a permit?
• In Queensland, does the small-scale rooming accommodation pathway apply, and can we realistically be through before it expires on 2 December 2026?
• What is the neighbour objection risk here, and does the density restriction in section 31 of the SDA Rules interact with anything in the planning approval, for example a condition limiting resident numbers?

What to ask your access consultant and SDA assessor

• Which design category does this design actually achieve, and where is it marginal?
• What has to be resolved before design stage certification, and what typically fails at final as-built stage that was fine at design stage?
• Given the design standard is under review, what is the risk that this design is certified under one edition and completed under another, and are transitional arrangements known?
• Does the onsite overnight assistance room as drawn meet the requirements for the separate amount, and does it compromise the bedroom count?
• For a robust dwelling, is the breakout room compliant as drawn, and what fit-out is genuinely required rather than merely conventional?
• Who else on this project could not act as the assessor because of the independence requirements?

What to ask your quantity surveyor

• What is the real premium of this design category over an equivalent market dwelling on this site, itemised rather than expressed as a percentage, and how much of it is additional floor area that generates no additional bedroom?
• What is the maintenance and replacement profile of a robust or high physical support dwelling over a twenty-year hold, and what sinking fund does that imply against the section 28 good-repair obligation?
• What contingency is appropriate given two rounds of independent certification and the possibility of remedial work between them?