A granny flat is a small, self-contained dwelling built on the same block as your main house. It typically includes a bedroom, bathroom, kitchen, and living area.

In Western Australia, most local councils allow granny flats up to 70–80m² in size, but this can vary depending on your lot size and council rules.

Generally, if your property meets minimum lot size and zoning requirements, you can. Your local council will confirm whether your block is suitable.

Yes. Most granny flats require development approval and a building permit. Some councils offer fast-track approvals for compliant designs.

Construction usually takes 3–6 months, depending on the design, materials, and whether you choose a custom or modular build.

Costs typically range from $120,000 to $200,000+, depending on size, finishes, and whether it’s custom-built or prefabricated.

No, the granny flat must be completed and inspected before it can be occupied.

Yes, you can rent it out to family, tenants, or via short-term rentals like Airbnb. Check council zoning and strata rules if applicable.

Most councils limit granny flats to one or two bedrooms, depending on the block size.

Yes. You can choose a custom design to match your home or select a pre-designed modular plan for a faster build.

Yes, granny flats are self-contained dwellings, so a kitchen and bathroom are standard features.

Absolutely. Matching rooflines, materials, and colours can make the granny flat blend seamlessly with your home.

Two-story granny flats are possible but often require stricter council approvals and may be restricted by lot size.

Most WA councils require a block of at least 450–500m², but rules vary depending on zoning and setbacks.

Setbacks usually range from 1–2 metres from the side or rear boundary, depending on council requirements.

Yes, but you may be limited in size, setbacks, and outdoor space. Some councils allow granny flats on blocks as small as 300–350m² with special approval.

Yes, but the total site coverage may be restricted by council rules. You may need to adjust the design or relocate structures.

Brick, timber, and steel frames are common. Modular prefab units are also popular for faster construction.

Yes. Many builders offer energy-efficient designs, solar panels, and water-saving features.

Yes. Prefab units are quicker to install, often cheaper, and still compliant with WA building codes.

Concrete slab foundations are most common, but piers or raised timber options may be used on sloped blocks.

Granny flats must comply with the Building Code of Australia (BCA), WA building regulations, and local council planning schemes.

Yes, a building permit is mandatory before construction starts. Your builder usually arranges this.

Rental income is generally allowed, but short-term rentals may be restricted in some council zones or strata schemes.

Special approvals may be required, and designs may be restricted to preserve the heritage or environmental features.

Yes, solar panels can be added, but council approval may be needed if visible from the street.

Yes. Most granny flats share water, electricity, and sewage connections with the main house, though separate metering is possible.

Yes, banks offer construction loans, equity loans, or refinancing options. A builder’s quote and council approval are usually required.

Currently, WA offers limited grants, but you may access incentives through energy-efficient building programs or first-home schemes.

Granny flats require standard maintenance and insurance. Utilities, property insurance, and council rates may increase slightly.

Yes. Granny flats are ideal for elderly family members, adult children, or rental income through platforms like Airbnb.

Yes. Many homeowners add granny flats after the main house is complete, provided the block size and council rules allow it.

Yes. A granny flat can increase property value and attract buyers seeking extra living space or rental income.