A secondary dwelling (commonly called a granny flat) is a self-contained dwelling established in conjunction with a principal dwelling on the same lot. It may be within, attached to or separate from the principal dwelling. Its legal classification comes from the approved use and documents, not its appearance or marketing name. Under the secondary-dwelling framework, the two dwellings remain on one lot.
Dunoon SAL 11328 covers approximately 30.3347 square kilometres and contains 11 mesh blocks in the supplied canonical locality record. SAL means the Australian Bureau of Statistics Suburbs and Localities geography. SAL boundaries approximate commonly recognised localities for statistical purposes; they are not cadastral, zoning or consent-authority boundaries and must not be confused with SA1 geography.
The 2021 Census Dunoon QuickStats recorded 840 people, 343 private dwellings and an average of 2.6 people per household. These are historical results from the 2021 Census, not current population, housing-supply or market measures. They provide limited locality context but cannot establish present demand, property values, planning rights or the suitability of a particular parcel.
AMESCorp commercial disclosure and privacy warning: AMESCorp is the commercial service provider promoted by this guide and may benefit if a reader purchases its services. This guide is general information, not legal, planning, financial, tax or investment advice. Independently verify all property information, professional advice, scope and pricing. Do not send personal information, title documents, plans, financial details or property data through an unsecured channel. No guarantees are provided.
Local granny-flat overview
The verified locality facts are limited. The supplied ABS geography records Dunoon entirely within the statistical LGA named “Lismore”. That statistical LGA name is distinct from the formal council organisation name, Lismore City Council. Geographic overlap does not establish that the council is the consent authority for every legal parcel. Confirm the street address, lot and deposited plan, responsible authority and current property mapping before applying council material.
If parcel verification confirms Lismore City Council as the responsible council, its development applications page and guide to the DA process provide official starting points for local application preparation. Their applicability remains subject to the legal parcel, proposal and planning pathway.
The statewide secondary-dwelling guidance says this form of development operates with an existing or proposed principal dwelling. It does not create a separately subdividable, separately titled or independently saleable residence. Anyone seeking separate ownership or later subdivision should obtain advice about the correct development classification rather than assuming a secondary dwelling can deliver that arrangement.
NSW guidance identifies residential zones R1, R2, R3, R4 and R5 as zones where secondary dwellings are permitted. Other zones may permit them through the applicable local environmental plan. Permissibility is only an initial planning question; it is not approval. Rural or non-residential land requires direct examination of the current local environmental plan because some instruments contain special rural-zone provisions, and residential-zone assumptions cannot safely be transferred to that land.
Begin property research with the NSW Planning Portal Spatial Viewer. Search the exact address to identify mapped zoning, planning instruments and controls, then reconcile the result with title and deposited-plan information. Also obtain the approval history for the principal dwelling and any garage, shed or other building proposed for conversion. An existing structure is not necessarily approved for habitation, even if it appears physically suitable.
Parcel verification should cover title restrictions, easements, covenants, boundaries, legal access, sewer and drainage assets, utility locations and relevant property mapping. Planning approval may not remove a private title restriction. Address-specific investigation is also necessary before discussing hazards or overlays: the locality record does not prove that a Dunoon property is affected by, or free from, any particular constraint.
Council rules and approval pathway
A secondary dwelling may proceed through a development application or, where every applicable requirement is satisfied, complying development. A development application is assessed by the responsible council against current planning instruments, local controls, site conditions and likely impacts. A complying development certificate may be issued by council or an appropriately registered certifier, but only for a proposal that meets the prescribed standards and is not excluded. The Department’s complying-development guidance explains this standards-based pathway and the certifier’s role.
For the Housing SEPP complying-development pathway, official guidance identifies a lot area of at least 450 square metres, except where the secondary dwelling is located entirely within an existing dwelling house. This is one eligibility test only. It is not a universal minimum for a council-assessed development application, and satisfying it does not establish complying-development eligibility.
The pathway assessment must use the current State Environmental Planning Policy (Housing) 2021, including Schedule 1, together with the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008. Check the exact proposal against mapped exclusions, development standards, the applicable local environmental plan, development control plan and any site-specific instrument. A registered certifier cannot waive an exclusion or planning control.
The current Housing SEPP contains site and floor-area provisions. Applicable floor area, height, setbacks, landscaping, site coverage and earthworks controls should be taken directly from the instruments governing the verified property and pathway, not from an old guide or a different development type. The Housing SEPP does not itself require additional parking for a secondary dwelling, but existing consent conditions, loss of approved parking, access design, driveway safety and vehicle-crossing requirements may still need resolution.
For either pathway, define whether the proposal is internal, attached, separate or a conversion. Confirm the lawful principal dwelling, existing approvals, title arrangement, service access and any relevant mapped controls. Ask the council or certifier what plans, reports, contribution-plan checks, waste arrangements, stormwater information and servicing-authority evidence are required. If Lismore City Council is verified as responsible, use its current DA guidance; electronic applications are lodged through the NSW Planning Portal online application service where applicable.
A concept plan, quotation, BASIX certificate or builder statement is not planning approval. Obtain the required consent or complying development certificate before starting work, follow approval conditions and arrange required construction inspections. Service NSW explains that an occupation certificate is required before occupying or using a new building, or using an existing building for a changed purpose. Confirm the inspection and certificate sequence with the appointed certifier for the approved project.
Costs and budgeting
There is no verified locality-wide construction price, council fee or utility allowance for Dunoon in the supplied evidence. Build a property-specific budget from completed investigations, coordinated documentation and comparable itemised quotes. Headline package prices are not useful unless their assumptions, inclusions and exclusions match the site and approval scope.
Organise the budget under separate headings for:
- title searches, surveys, service locating and preliminary investigations;
- design, engineering and specialist reports;
- application, Planning Portal, council and certifier charges;
- contributions where an applicable plan requires them;
- demolition, excavation, retaining, spoil removal and site preparation;
- building work, fixtures, finishes and BASIX commitments;
- sewer, water, electricity, telecommunications and stormwater work;
- access, paths, driveways, fencing and other external works;
- inspections, certificates, insurance and handover documents; and
- an allowance based on identified unresolved risks rather than a generic percentage.
Slope, ground conditions, machinery access, service distances, drainage, trees and existing-building work can materially alter the scope. A conversion may require structural upgrading, waterproofing, insulation, ventilation, fire-safety work and new services. Investigate these matters before treating conversion as a lower-cost option.
Give tenderers the same survey, drawings, specifications and reports. Require each quote to identify provisional sums, prime-cost items, authority charges, service connections, external works and responsibility for approvals, engineering, BASIX, certification and occupation-certificate documents. Verify current council and authority charges directly for the actual proposal.
The Building Commission NSW contract guidance states that residential building work costing more than $5,000 requires a written contract, while work costing more than $20,000 requires the more extensive large-job contract. The maximum deposit is 10 per cent. Read the Consumer Building Guide, document the full scope and align progress payments with completed work.
Home building compensation cover applies to residential building work valued at $20,000 or more, including GST, subject to the official rules. Obtain the project-specific certificate and verify its details using HBC Check before making a payment where cover is required. Recheck the statutory contract and warranty information when procuring the work.
Design and site considerations
Start design after confirming the survey, property controls and likely approval pathway. Position the secondary dwelling in a functional relationship with the principal dwelling while providing practical privacy, daylight, ventilation and maintenance access. Review entrances, windows and outdoor areas together so the two households are not unnecessarily exposed to overlooking, noise or circulation conflicts.
Test the layout for usable private open space, waste storage, clothes drying, mail delivery, pedestrian access and any parking impact identified during pathway assessment. Consider how occupants, visitors and emergency or maintenance workers will reach the secondary dwelling. An arrangement that fits on a plan may still be unsuitable if access passes through the principal dwelling’s private areas or service equipment cannot be maintained safely.
Locate sewer, drainage, water, electricity and telecommunications infrastructure early. Check easements and authority protection requirements, available connection points and system capacity. Establish a lawful stormwater strategy appropriate to the property; an informal outlet or discharge toward neighbouring land should not be assumed acceptable. Where on-site wastewater is relevant, investigate the existing approval, capacity and land-application requirements with an appropriately qualified adviser and responsible authority.
Address a constraint only when official property mapping or site investigation makes it relevant. The Spatial Viewer may indicate that further work is needed for matters such as heritage, bushfire, flooding, biodiversity or another mapped control. A qualified consultant may then need to assess the proposal, but the required report should follow verified site evidence rather than a generic locality inventory.
BASIX is part of design development, not an exercise to leave until documentation is complete. The Planning Portal BASIX guidance covers water, energy use and thermal performance. Its secondary-dwelling project guidance distinguishes conversions, new attached or separate secondary dwellings, and projects involving new principal and secondary dwellings together. Select the project type that matches the approved scope and carry all certificate commitments into drawings, specifications and construction checks.
Prefabricated, modular or relocatable construction does not bypass planning, building, BASIX or certification requirements. Likewise, physical room dimensions do not establish that a shed or garage may lawfully become accommodation. Check approval records and obtain any required change-of-use, development and construction approvals before conversion work begins.
Rental and investment considerations
Consider rental use only after confirming lawful approval, construction certification and occupation. Retain the consent or complying development certificate, approved plans, BASIX material, inspection records, warranties and occupation certificate. These documents help an owner, insurer, manager or future purchaser understand what was authorised and how the work was completed.
If the approved secondary dwelling is let under a residential tenancy, use current NSW Fair Trading residential tenancy guidance and the Residential Tenancies Act 2010. Check the current standard agreement, required information, condition-report and bond processes, repair and safety duties, access rules and procedures for changing or ending the tenancy when the agreement is prepared.
Do not treat family occupation, a licence, room letting, short-term accommodation and a standard residential tenancy as interchangeable. The proposed arrangement may have different planning, tenancy, insurance or management consequences. Obtain advice for the intended use and check whether the approval documents impose relevant conditions.
Plan how each household will use access, outdoor areas, waste facilities and shared spaces. Define responsibility for gardens, repairs and service access. Establish how electricity, water, internet and other services will be supplied and lawfully charged. Separate metering may be worth investigating, but authority requirements, tenancy law, feasibility and installation work should be checked before it is specified.
The 2021 Census figures cited in the introduction do not demonstrate present rental demand or achievable rent. Obtain current comparable evidence and distinguish advertised asking prices from completed transactions or achieved rents. Test the proposed arrangement against finance costs, insurance, maintenance, management, compliance expenses and periods without rent. Seek advice suited to the owner’s circumstances from finance, insurance, taxation, legal and property-management professionals before making an investment decision.
Choosing a granny-flat builder
Complete preliminary planning and site investigations before requesting final tenders so builders price a consistent, realistic scope. Identify the legal entity that would sign the contract, then use the official NSW builder and tradesperson licence check to verify its current licence status, category and conditions. An ABN, industry membership, online review or salesperson’s statement is not a substitute for that register check.
Ask for recent references involving comparable secondary dwellings, approval pathways, access and servicing work. Inspect completed projects where possible and ask owners about communication, site supervision, variations, defects and handover. References assist with qualitative assessment, while licence, contract and insurance evidence provide separate statutory checks.
Compare tenders against the same documents and examine:
- the contracting entity and licensed supervisor;
- drawings, specifications, inclusions and exclusions;
- provisional sums and prime-cost items;
- demolition, excavation, retaining and spoil removal;
- sewer, stormwater, electrical and other connections;
- approval, BASIX, engineering and certifier responsibilities;
- variation procedures and extension-of-time terms;
- progress-payment stages, defect processes and warranties; and
- certificates, manuals and occupation documents required at handover.
Clarify who bears the risk if service locations, ground conditions or authority requirements differ from initial assumptions. Resolve investigable uncertainties before contract rather than leaving broad allowances. A low headline quote may omit essential site work, external works, fees or certification.
Use the appropriate written contract, read the Consumer Building Guide and ensure verbal representations are recorded in the signed documents. Do not sign blank sections. Require variations to be documented and priced under the contract before the varied work proceeds, except where an urgent legal or safety issue requires another response.
Verify statutory warranty information and the project-specific HBC evidence where applicable. Keep payments linked to completed stages and retain invoices, approvals, inspection records and correspondence. Before final payment, inspect the work, record defects, collect warranties and certificates, and confirm that the certifier has the documents needed for occupation. Obtain independent legal, building or quantity-surveying advice if the contract scope or risk allocation is unclear.
Planning and feasibility checklist
- Confirm the address, lot, deposited plan, title and lawful principal dwelling.
- Verify the responsible council and consent authority for the parcel.
- Search the Spatial Viewer for zoning, instruments and mapped controls.
- Review the current local environmental plan and development control plan.
- Obtain the title search, survey, service plans and approval history.
- Investigate easements, restrictions, access, drainage and relevant constraints.
- Define the proposal as internal, attached, separate or a conversion.
- Test both approval pathways against current instruments and exclusions.
- Confirm BASIX, reports, fees, contributions and submission documents.
- Compare complete, itemised quotes on a like-for-like basis.
- Check licences, contract terms, warranties and HBC evidence.
- Obtain approval before work and complete required inspections.
- Secure the occupation certificate before occupation or use.
- Use current Fair Trading documents if creating a tenancy.