Planning Maps / Areas / Willoughby / Castlecrag

Castlecrag zoning & planning overlays

A planning-constraint profile of Castlecrag (Willoughby, NSW) - 1.47 km², mapped from live council and state overlay data. This suburb is highly constrained on the overlays we hold - no flood mapping covers this suburb, so this is not a suburb-wide verdict.

Elevation hillshade with street names, clipped to Castlecrag's boundary, with the bushfire and environmental overlays drawn on top. It shows where constraints fall; the interactive map shows them on your exact address. No flood layer is drawn because we hold no flood mapping for this area.

Castlecrag at a glance

Parcels 1,248 Median lot 704 m² Mapped easements 4 Bus stops 31

How Castlecrag is zoned

Environmental Living 54%
Environmental Conservation 25%
Low Density Residential 15%
Public Recreation 3%
Infrastructure 2%
Local Centre 1%

Buying in Castlecrag? The zoning, flood and bushfire lines on the section 10.7 certificate attached to the contract are mapped controls - see our s10.7 certificate guide.

Across its 1.47 km², Castlecrag is highly constrained by the planning overlays we hold. We hold no flood mapping covering this suburb, so no flood figure is shown - that is a gap in our data, not an all-clear. Of what is mapped, 44% is flagged bushfire-prone. There are 51 heritage-listed sites on record, and the dominant land-use zone is Environmental Living. The median lot measures about 704 m² across 1,248 parcels. These figures are suburb-wide - the overlays that actually apply to a given lot can differ block to block, which is what a property-level check tells you.

Who lives in Castlecrag

Census 2021 figures published by the ABS for the Castlecrag suburb boundary itself, not a wider region.

Population
2,965
usual residents, 2021
Median age
47
years
Median household income
$4,675
per week, Willoughby suburb typical $3,196
Median rent
$1,010
per week, Willoughby suburb typical $671
Median mortgage
$4,333
per month
Household size
3.0
people, average

Socio-economic standing

ABS SEIFA 2021 ranks every Australian suburb. Decile 1 is the most disadvantaged tenth of the country, decile 10 the least.

Advantage and disadvantage (IRSAD) Decile 10
most disadvantagedleast disadvantaged

Score 1195, and decile 10 within New South Wales. The national average is 1000.

Relative disadvantage (IRSD) Decile 10
most disadvantagedleast disadvantaged

Age profile

Share of Castlecrag's 2,965 residents in each ABS age band.

0-4 3.3%
5-14 14.9%
15-19 9.8%
20-24 6.0%
25-34 4.0%
35-44 9.1%
45-54 18.9%
55-64 15.2%
65-74 11.6%
75-84 5.0%
85+ 2.1%

Population trend, 2001 to 2025

Estimated resident population of Castle Cove - Northbridge, the wider ABS statistical area containing Castlecrag. There is no annual population series published at suburb level, so this describes the surrounding area rather than Castlecrag itself.

12,615 in 2001 to 13,592 in 2025, up 8%.

Source: Australian Bureau of Statistics. Census of Population and Housing 2021 (General Community Profile) and SEIFA 2021, both published at the Suburbs and Localities level; Regional Population (estimated resident population) at Statistical Area Level 2. Used under CC BY 4.0. Census counts of small populations are randomly adjusted by the ABS to protect confidentiality, so figures for small suburbs are indicative.

Castlecrag data sources and coverage

Every figure below is an aggregate for the suburb boundary. “Not mapped” means LayeredGeo does not hold a source layer covering this suburb; it is never an all-clear for a particular property.

DatasetCoveragePublisher
Flood mappingNot mappedNSW Government spatial services, NSW ePlanning and published council flood studies
Bushfire-prone mappingMappedNSW Government spatial services, NSW ePlanning and published council flood studies
ZoningMappedNSW Government spatial services, NSW ePlanning and published council flood studies
Heritage and environmentMapped where publishedNSW Government spatial services, NSW ePlanning and published council flood studies
DemographicsAvailableAustralian Bureau of Statistics (2021 Census and SEIFA)

Profile last materially updated 5 August 2026. See the methodology and full source list. Source data changes over time and critical decisions should be checked with the responsible authority.

Check a specific Castlecrag address

See exactly which overlays touch a single property - the interactive map is free. Need it on paper? A full planning PDF is just $9.

See what's in the $9 report →

Castlecrag planning - frequently asked

Is Castlecrag flood-prone?

We don't yet hold flood mapping covering Castlecrag, so this page can't say how much of the suburb is flood-affected - that is a gap in our data, not an indication that the suburb is free of flood risk. Willoughby is the authority to check for flood mapping in this area. Flood overlays vary block to block, so whether a particular lot is affected needs a property-level check.

Is Castlecrag bushfire-prone?

Yes - around 44% of Castlecrag is mapped as bushfire-prone, compared with a Willoughby average of 26%. A bushfire-prone designation can trigger additional building requirements, so check the specific address.

What is the zoning in Castlecrag?

The dominant planning zone in Castlecrag is Environmental Living, though the suburb also includes Environmental Conservation and Low Density Residential. Zoning sets what you can build and do on a site, and can differ lot by lot.

Does Castlecrag have heritage-listed places?

Castlecrag has 51 heritage-listed places on record. Heritage listing affects what you can alter or demolish, so confirm whether a specific property is listed or near a heritage place.

What is the typical lot size in Castlecrag?

Across 1,248 surveyed parcels in Castlecrag, the median lot size is about 704 m². There are also 4 registered easements mapped in the suburb - an easement can restrict where you can build, so always check the title and overlays for the specific lot.

Does Castlecrag have a train station?

There is no train station inside Castlecrag itself. The suburb is served by 31 bus stops.

What is the population of Castlecrag?

At the 2021 Census Castlecrag had 2,965 usual residents, with a median age of 47 and an average household size of 3.0 people. The wider Castle Cove - Northbridge statistical area, which contains Castlecrag, went from 12,615 people in 2001 to 13,592 in 2025, up 8%. ABS publishes no annual population series for individual suburbs, so that trend describes the surrounding area rather than Castlecrag alone.

Is Castlecrag an advantaged suburb?

On the ABS SEIFA 2021 index of relative socio-economic advantage and disadvantage (IRSAD), Castlecrag scores 1195 and sits in decile 10 of 10 nationally and decile 10 within New South Wales - decile 1 being the most disadvantaged tenth of Australian suburbs and decile 10 the least. The national average score is 1000. SEIFA summarises income, education, occupation and housing across the whole suburb, so it describes the area, not any particular household in it.

What is the median household income in Castlecrag?

Median household income in Castlecrag was $4,675 a week at the 2021 Census, against $3,196 for the typical suburb in Willoughby. Median rent was $1,010 a week and the median mortgage repayment $4,333 a month. These are 2021 Census figures and have not been indexed to today.

Do I need a planning report for a Castlecrag property?

A Castlecrag planning report pulls every overlay - zoning, flood, bushfire, heritage and environmental - that touches a single lot, on live council and state data. The interactive map preview is free; a full PDF report is $9.

Compare nearby suburbs

Nearby suburbDistanceFlood mappedBushfire-prone
Northbridge 1.2 km Not mapped 29%
Middle Cove 1.3 km Not mapped 74%
Willoughby East 1.4 km Not mapped 0%
Middle Harbour
Unincorporated - Sydney Harbour Area
1.6 km Not mapped 29%
Castle Cove 1.8 km Not mapped 73%
North Willoughby 1.9 km Not mapped 0%
Willoughby 2.0 km Not mapped <1%
Seaforth
Northern Beaches
2.3 km Not mapped 37%
Naremburn 2.5 km Not mapped 6%
Cammeray
North Sydney
2.6 km Not mapped 10%

See all Willoughby suburb profiles →