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 that dwelling. Its legal classification depends on the approved use and documents, not its marketing name or construction method.
This guide separates the few verified facts about Congo from statewide planning guidance. The locality record and Census geography cannot establish a parcel’s council, zoning, constraints or development rights. Those matters require the legal address, lot and deposited plan, title information, current planning instruments and property-specific assessment.
AMESCorp commercial disclosure and privacy warning: AMESCorp is the promoted commercial service provider and may have a commercial interest in enquiries or services arising from this guide. Independently verify its scope, advice, pricing and any claimed approvals. No guarantees are provided. Do not send AMESCorp—or any unverified recipient—personal information, title documents, financial records or detailed property data unless you have assessed why it is needed, how it will be used and the applicable privacy arrangements.
Local granny-flat overview
Congo is identified in the supplied Australian Bureau of Statistics record as Suburbs and Localities (SAL) code 11008. SAL is the ABS Suburbs and Localities geography: it represents statistical approximations of officially recognised locality boundaries and is not a cadastral or planning boundary. It must not be confused with SA1. The supplied locality profile covers about 10.1192 square kilometres and four mesh blocks.
The supplied spatial record places the entire SAL area within the ABS statistical LGA named Eurobodalla. That statistical LGA name is distinct from the formal council organisation name, Eurobodalla Shire Council. The overlap is a useful research lead only; it does not prove that the council administers a particular legal parcel. Confirm the address and lot/DP before applying council material.
The 2021 Census QuickStats for Congo reported 253 people, 70 families, 158 private dwellings and a median age of 48. These are historical 2021 Census values for the SAL, not current population or property-market evidence. The small statistical base and elapsed time make it unsafe to derive present rental demand, household preferences, development capacity or investment performance from them.
Statewide, the official term is secondary dwelling. NSW secondary-dwelling guidance says the dwelling must be self-contained, associated with a principal dwelling and located on the same site. The secondary-dwelling pathway does not create a separately subdividable residence. A freestanding structure is not automatically a secondary dwelling, and a garage, shed or studio cannot be treated as approved accommodation without checking its approval history and authorised use.
The same guidance says secondary dwellings are permitted in residential zones R1, R2, R3, R4 and R5 and may be permitted in other zones under the relevant local environmental plan. This is statewide permissibility guidance, not evidence about Congo land. Rural and other non-residential land requires close review of the local environmental plan because special provisions can differ from residential-zone rules.
Start locality research with the NSW Planning Portal Spatial Viewer, then verify its results against the in-force instruments and formal property records. If the legal parcel is confirmed as being under Eurobodalla Shire Council, its planning guides and tools provide the official local entry point. Council identifies the Eurobodalla Local Environmental Plan 2012 on its local environmental plans page, but that instrument’s application, zone and controls must be verified for the parcel.
The available locality evidence does not establish typical lot dimensions, services, hazards, terrain or planning potential. Avoid suburb-wide assumptions. Useful feasibility begins with a title search, survey, planning information and existing approval records rather than a postcode, locality label or neighbouring project.
Council rules and approval pathway
Two potential pathways exist: development consent through a council-assessed development application, or a complying development certificate (CDC) issued by council or a registered certifier when every statutory requirement is satisfied. NSW complying-development guidance describes complying development as standards based; a certifier cannot waive eligibility criteria, mapped exclusions or development standards.
For the Housing SEPP complying-development pathway, NSW guidance identifies a minimum lot area of 450 square metres, except where the secondary dwelling is located entirely within an existing dwelling house. This is one bounded CDC criterion only. It is neither a universal minimum for a development application nor proof that CDC is available.
Test a proposed CDC against current Schedule 1 of the State Environmental Planning Policy (Housing) 2021, the applicable provisions of the State Environmental Planning Policy (Exempt and Complying Development Codes) 2008, mapped exclusions and all site standards. Use the current in-force legislation rather than superseded Affordable Rental Housing SEPP material or generic checklists.
If Eurobodalla Shire Council is verified for the parcel, check the Eurobodalla LEP, applicable development control plans, property tools and current application requirements. Council’s development application process states that DAs are lodged online through the NSW Planning Portal. Also establish whether any site-specific instrument, contribution plan, local fee, waste requirement, stormwater policy, driveway or vehicle-crossing process, or water and sewer authority requirement applies. A council officer or appropriately registered certifier should confirm the suitable pathway before it is described as complying development.
The Housing SEPP does not itself require additional parking for a secondary dwelling. Nevertheless, existing consent conditions, displacement of existing parking, access safety, manoeuvring and applicable design controls still require review.
Parcel verification should cover the title and deposited plan; easements, covenants and restrictions; legal access; sewer, drainage and utility assets; and the lawful approval of the principal dwelling and any structure proposed for conversion. Planning consent may not remove private title restrictions. Official address-level records should also be checked for mapped or property-specific matters such as heritage, bushfire, flooding, biodiversity, coastal hazards, acid sulfate soils, contamination and mine subsidence. Mentioning these as due-diligence categories does not suggest that any applies in Congo.
Once approval is obtained, comply with its conditions, certification requirements and inspections. Service NSW explains that an occupation certificate is required before occupying or using a new building or changing the use of an existing one. Confirm the required certifier and documents for the approved project. A concept, quote, BASIX certificate or builder statement does not replace planning or building approval.
Costs and budgeting
There is no verified suburb-wide build price for Congo in the supplied evidence. A useful budget must follow site investigation, pathway testing and a documented scope. Access, levels, ground conditions, service routes, existing structures, required reports and finish selections can materially alter the work.
Build the estimate under separate headings:
- property records, survey and service investigations;
- design, engineering and specialist reports;
- application, Planning Portal and certifier charges;
- council contributions and authority fees, if applicable;
- demolition, excavation, retaining and site preparation;
- construction, fixtures and finishes;
- stormwater, wastewater, water, power and communications;
- access, paths, fencing, landscaping and waste removal;
- certificates, inspections, insurance and finance expenses; and
- a project contingency based on identified risks rather than a generic percentage.
Resolve services early. Confirm asset locations, available capacity, lawful stormwater discharge, connection approvals and responsibility for upgrades. For a conversion, investigate the existing building’s approval status, structure, waterproofing, fire safety, ventilation, insulation and services before pricing. A structure that physically fits the proposed rooms may still require extensive work or a different approval approach.
Give tenderers the same drawings, specifications, reports and site information. Require itemised quotes that identify exclusions, provisional sums, excavation assumptions, utility allowances, external works, approval responsibilities, BASIX items and authority charges. Separate firm prices from allowances so that headline package pricing does not hide unresolved scope.
Building Commission NSW contract guidance requires a written contract for residential building work costing more than $5,000, with more extensive large-job contract requirements above $20,000. The maximum deposit is 10%. Read the Consumer Building Guide before signing, check the proposed progress-payment stages against completed work and ensure variations are documented.
Home building compensation cover applies where required for residential work valued at $20,000 or more including GST. Before paying money or allowing work to begin, use the official HBC Check to verify the certificate and confirm that its legal entity, site and work align with the contract. Recheck current fees, forms and statutory requirements immediately before commitment because they can change.
Design and site considerations
Begin with an accurate survey and a clear classification: will the proposal sit within, attach to or stand separately from the principal dwelling, or convert an existing structure? Record boundaries, levels, structures, significant trees, access, easements and known services. Confirm that the principal dwelling and any conversion candidate are lawfully approved for their existing uses.
Test the layout for privacy, overlooking, daylight, ventilation, noise separation, usable outdoor space, clothes drying, waste storage and safe pedestrian access. Plan how occupants of both dwellings will share or separate entrances, paths, driveways and maintenance areas. Where the proposal affects existing parking or vehicle movement, resolve those consequences with the relevant decision-maker.
Check floor area, setbacks, height, landscaped area, site coverage and earthworks under the exact approval pathway and current instruments. Do not import a standard from another council, another development type or an older planning policy. Design documentation should also reconcile title restrictions, asset clearances, stormwater and wastewater arrangements, utility requirements and any verified property constraint.
Use mapping to identify issues for investigation, but obtain specialist input only where address-level evidence or the approval pathway requires it. For example, a verified tree, hazard or heritage control may affect siting, construction materials, reports or access. This property-led method is more reliable than using an interchangeable list of possible constraints.
BASIX guidance covers water, energy use and thermal performance for applicable residential development. The Planning Portal’s secondary-dwelling BASIX guidance distinguishes conversions, new secondary dwellings, and projects containing a new principal and secondary dwelling. Select the correct classification and incorporate commitments into orientation, glazing, shading, insulation, ventilation, fixtures, services, drawings and the building contract.
Do not assume modular, prefabricated or relocatable construction avoids planning, building, BASIX or certification requirements. Likewise, apparent structural soundness does not authorise habitation of an outbuilding. Align the selected building system with the approval, site access, engineering, service connections and occupation-certificate documentation.
Rental and investment considerations
Consider rental use only after verifying lawful approval, completion in accordance with that approval and the required occupation certificate. A utility connection, builder handover or marketing description is not evidence that premises may lawfully be occupied.
The principal and secondary dwellings remain on the same lot under this planning pathway. That has practical implications for access, insurance, lending, valuation, maintenance and future dealings with the land. Obtain advice based on the actual title and ownership structure rather than modelling the secondary dwelling as a separately saleable property.
Where the approved premises are let under a residential tenancy, use current NSW Fair Trading guidance on residential tenancy agreements and the Residential Tenancies Act 2010. Check the current standard agreement and requirements for bonds, condition reports, disclosure, repairs, safety and notices. Family occupancy, licences, boarder arrangements and short-term accommodation may be treated differently, so classify the intended arrangement before preparing documents.
Operational planning should address separate access, visual and acoustic privacy, deliveries, bins, clothes drying, emergency arrangements and access for repairs. Document responsibility for gardens, shared paths, driveways and common services. If utilities are shared, obtain advice on lawful metering, billing and on-charging rather than adopting an informal formula.
The 2021 Census figures above do not establish current demand or achievable rent. Obtain recent, genuinely comparable local evidence and distinguish advertised asking prices from completed leasing evidence. Test finance, insurance, taxation and property-management arrangements with appropriately qualified advisers using the approved design, title and intended occupancy. Use scenario analysis for vacancies, repairs and operating costs instead of relying on a forecast return.
Choosing a granny-flat builder
Identify the exact legal entity offering to contract, then use the Service NSW tool to check the builder or tradesperson licence. Match the current licence holder, category and number to the proposed work and contract. An ABN, industry membership, website badge or review rating is not a licence check.
Request recent references for comparable secondary dwellings, preferably involving similar access, services and construction. With owners’ permission, inspect completed work and ask about communication, variations, site-cost control, defects, documentation and after-completion service.
Compare tenders against one issued scope. Review:
- specifications, inclusions, exclusions and provisional sums;
- site preparation, access, excavation and retaining assumptions;
- stormwater, utility and authority responsibilities;
- approvals, consultants, certification and inspections;
- BASIX products and performance commitments;
- external works, waste removal and making good;
- variation and extension-of-time procedures;
- defects, statutory warranty information and handover records.
Establish whether each price uses approved construction documents or an early concept. Put responsibility for consultant coordination, authority responses, certificates and occupation-certificate material in writing. Read the Consumer Building Guide, use the appropriate written contract, keep progress claims tied to completed stages and verify statutory warranty information applicable to the work. Record agreed variations, including price and schedule effects, before varied work proceeds where practicable.
Complete the HBC verification described in the budgeting section before the relevant payment or commencement point. Assess the total documented delivery scope, not merely the lowest headline amount, and clarify every material allowance or exclusion before signing.
Planning and feasibility checklist
- Confirm the address, lot/DP, title and lawful principal dwelling.
- Verify the responsible council from parcel-level records.
- Check the zone and mapped controls in the Spatial Viewer.
- Review the current LEP, DCPs and site-specific instruments.
- Obtain the title, survey, service plans and approval history.
- Investigate easements, restrictions, access, drainage and utilities.
- Verify only those hazards and overlays mapped for the parcel.
- Define the proposal as internal, attached, separate or a conversion.
- Test DA and CDC pathways with council or a registered certifier.
- Confirm design standards, reports, BASIX and application documents.
- Verify current fees, contributions and authority requirements.
- Compare itemised quotes on an identical documented scope.
- Check licences, contract terms, warranties and HBC evidence.
- Obtain approval before work and complete required inspections.
- Obtain the occupation certificate before occupation or use.
- Use current Fair Trading processes if the dwelling will be rented.