Dual Occupancies – Northern Beaches Council (Former Warringah Area)

Dual occupancies, or what are more commonly known as a ‘duplex’ when attached, are defined as two dwellings on a single lot of land. Dual occupancies have historically been prohibited development on land zoned R2 Low Density Residential within the former Warringah Council Area, now part of the wider Northern Beaches Council. However, recent changes to NSW legislation in response to the ongoing NSW housing crisis have expressly permitted dual occupancy development on land zoned R2 Low Density Residential across the state, overriding the local Council prohibitions on the use in the R2 zone, including within the former Warringah Council Area.

So, what has driven the recent state wide change in permissibility, how are these development applications assessed, how will the local Council planning framework change in response to these state wide controls, and what implications does this have on your property? We’ll explore these topics in depth below.

State Wide Permissibility of Dual Occupancies

Published on the 28 February 2025, Stage 2 of the NSW Governments new Low and Mid rise housing policy was implemented into the State Environmental Planning Policy (SEPP) (Housing) 2021, under Chapter 6 Low and mid rise housing. This policy came into effect immediately upon publication and follows the implementation of Stage 1 of the reforms on 01 July 2024.

This policy broadly aims to encourage and facilitate a higher density of homes within appropriate areas in Sydney and across the state in response to the ongoing NSW housing crisis, which, is the biggest single cost of living pressure people in NSW are currently experiencing[1].

The bulk of the provisions within the Low and Mid rise housing policy apply only to development within what is referred to as “low and mid rise housing areas”, hereafter referred to as ‘LMR areas’. These LMR areas encompass an 800-meter walking distance from identified town centres and railway, metro, and light rail stations. There a 171 of these identified areas across NSW, with the bulk located within the Greater Sydney metropolitan area. The few LMR areas outside of Sydney stretch as far North as Newcastle and Maitland and as far south as Nowra.

Specified residential development within these LMR areas, including dual occupancies, multi-dwelling housing (town houses), and residential flat buildings (apartments), benefit from changes in permissibility and what are referred to as “non-discretionary development standards”. These non-discretionary development standards are essentially state implemented benchmarks that, when achieved on applicable sites, prevent the Council from refusing a development application (DA) based on non-compliance with those standards (as set out in Section 4.15 (2) of the Environmental Planning and Assessment Act 1979). These non-refusal standards pertain to aspects such as maximum floor space ratio, building height, parking provision, site area, lot width, and Torrens-title subdivision.

Further to the provisions afforded to specified residential development within these LMR areas, the Low and Mid rise housing policy has introduced a blanket provision under Section 166 of the SEPP (Housing) 2021 permitting dual occupancy development on all land zoned R2 Low Density Residential. Importantly, this blanket permissibility applies across the entire state and not just development within LMR areas, save for specified excluded areas identified within Section 164 including bushfire prone land, flood prone land (within certain Council areas), land which contains a heritage item, land within areas of high aircraft noise (ANEC 25 or greater), and others.

[1] https://www.nsw.gov.au/media-releases/addressing-housing-crisis-nsw

Whilst this blanket permissibility has made previously prohibited development permissible, the SEPP does not provide the detailed controls that Council use to assess development. This begs the question; how will Council assess an application for a development for which they have no controls?

How are these applications assessed for development that was previously prohibited

In time, Councils across will update both their Local Environmental Plans and Development Control Plans to harmonise with the LMR provisions of Chapter 6 of the SEPP (Housing) 2021. However, in the interim Councils will need to determine how to assess these development applications within the current planning framework.

In the case of development within the former Warringah Area (Northern Beaches Council) there is no dedicated chapter or controls within the Warringah Development Control Plan (DCP) for dual occupancy development in the R2 zone. The DCP does however contain general controls which can be broadly applied to dual occupancy development, although this is not ideal.

Where the DCP is entirely silent on an aspect of the development, or where a control may not be entirely applicable, external guidelines are required to make an informed assessment. Fortunately, the Low Rise Housing Diversity Design Guide for Development Applications (hereafter referred to as the “Design Guide”), published by the NSW Government in July of 2020, serves this exact purpose. The Guide provides consistent planning and design standards for low rise diverse residential dwellings across NSW. This includes provisions for dual occupancy development (attached), manor houses, and multi dwelling housing. Whilst the dual occupancy controls within the Design Guide specifically relate to attached development, it is reasonable to apply these controls to all dual occupancy development, both attached and detached, given the total absence of applicable DCP controls in certain areas.

As this is a developing topic, you should consult with your local Council or town planner if you are unsure what controls will guide your development.

How will the local Council planning framework change in response to these state wide controls?

In response to the implementation of the Low and Midrise housing policy Northern Beaches Council has advertised, and will soon implement, amendments to the current DCP’s (Warringah, Manly, and Pittwater). These amendments provide an additional chapter of controls (Advertised to be part G10 of the DCP) specifically designed to guide Low and Mid-Rise Housing development and bridge the gap until the comprehensive Northern Beaches DCP comes into force, which is anticipated by mid 2026[2]. Notable additions within Part G10 are:

• Detached dual occupancies are heavily discouraged aside from large lots;
• Front and back dual occupancy arrangements are discouraged and side by side are encouraged;
• New side setback, deep soil area, and tree planting controls have been added.

In addition to the DCP changes, the LEP will also be updated to harmonise with the SEPP (Housing) 2021. The forthcoming consolidated Northern Beaches Local Environmental Plan (LEP), which is yet to be publicly exhibited as of time of writing, will presumably permit dual occupancy development within R2 Low Density Residential zones across the entire local government area, and may implement separate standards for such development (FSR, building height, etc.).  However, this is currently speculation and we will need to wait for the draft document to enter the public exhibition period for further information, likely in later 2025 or early 2026.

What do these changes mean for your property?

So how does this impact your property within the former Warringah local government area, zoned R2 Low Density Residential? Well, provided your property does not fall within the exclusion criteria listed in Section 164 of the SEPP (Housing) 2021, then you can now consider a dual occupancy. Permissibility on its own however does not automatically entitle your site to a dual occupancy development. Other key factors such as site area, frontage width, existing trees, bushfire prone land, flood affected land, heritage affectation, and many other factors impact whether development is feasible. If unsure, it is often prudent to consult with a town planner to confirm if your site is suitable for a dual occupancy development and, if so, what design factors to consider.

Further to the above, if your site is located within an identified LMR area and outside of the exclusion criteria, you are likely able to benefit from the aforementioned non-discretionary development standards and potentially other development options, such as multi-dwelling housing (town houses) or a residential flat building (apartments). To check if your site is located in an LMR area the NSW Government has created this online tool. Note, that the mapping associated with the online tool is only approximate and walking distances should be verified should there be any uncertainty.

 Figure 1: Low and Mid-Rise Housing Policy Indicative Map – Former Warringah Area and surrounds

Conclusion

The introduction of the Low and Mid Rise Housing Policy under SEPP (Housing) 2021 has opened a new pathway to dual occupancy development in the former Warringah Council area and throughout NSW, driving progress in housing availability and reshaping property development potential on the Northern Beaches. In response, Northern Beaches Council is updating its DCPs to include specific controls for low and mid-rise housing, with a consolidated DCP and LEP anticipated by mid-2026 to align with Chapter 6 of the SEPP (Housing) 2021 amongst other changes. Property owners can explore dual occupancy opportunities if their sites meet zoning and exclusion criteria, unlocking new development potential in the region.

Please note that the above information is, to my knowledge, correct as of the time of writing. As this is a developing topic you should ensure you check with your local Council or town planner for the latest information.

[2] https://yoursay.northernbeaches.nsw.gov.au/planning-our-sustainable-future/local-environmental-plan-and-development-control-plan

In a significant shift driven by the NSW Government’s push to increase housing supply across Sydney, dual occupancies are now permissible in Ku-ring-gai Council, whether council likes it or not. Whilst Ku-ring-gai has traditionally been known for its strict planning controls and resistance to increasing density, these statewide planning reforms are aimed at tackling the housing crisis. For investors, developers and home owners, this opens the door for valuable development opportunities in one of Sydney’s most desirable areas.

Permissibility of Dual Occupancies:

Dual occupancies have been and still are listed as a prohibited development under the Ku-ring-gai Local Environmental Plan except for a small number of properties listed in Schedule 1 for historical reasons. They are now however permissible generally across the R2 zone by Section 166 of the State Environmental Planning Policy (Housing) 2021, which states “Development for the purposes of dual occupancies or semi-detached dwellings is permitted with development consent on land to which this chapter applies in Zone R2 Low Density Residential.” It should be noted that State Environmental Planning Polices override Local Environmental Plans. Section 164 should be referred to confirm that the chapter applies to your land. Exclusion of your land from this chapter includes, but is not limited to:

• Bushfire prone land
• Heritage item
• Land which Transport Oriented Development applies
• Land identified as Accelerated TOD Precinct

How are they assessed:

The relevant controls in the Ku-ring-gai Local Environmental Plan 2015 and Ku-ring-gai Development Control Plan are still applicable and will be considered in the assessment of dual occupancies. For example, the floor space ratio permitted on your land remains as an applicable development standard.

Clause 4.4 Floor Space Ratio

The following clauses are found within the Ku-ring-gai LEP at Clause 4.4.

(2)  The maximum floor space ratio for a building on any land is not to exceed the floor space ratio shown for the land on the Floor Space Ratio Map.

(2A)  Despite subclause (2), the floor space ratio for a building on land in Zone R2 Low Density Residential where the site area is within a specified range in Column 1 of the table to this subclause must not exceed the ratio specified opposite in Column 2 of the table.

(2B)  Despite subclause (2A), if a dual occupancy (detached) is permissible on the land, the floor space ratio for the dual occupancy (detached) must not exceed 0.4:1.

See the following link to access Clause 4.4 of the KLEP 2015

Subclause (2A) applies to all buildings in the R2 zone, including attached dual occupancies. Subclause (2B) was intended to be applied to dual occupancies permissible under Schedule 1 of the LEP. Now that dual occupancies are permissible, one could argue that the wording of this clause implies that all detached dual occupancies can benefit from an FSR of 0.4:1. However, this is all likely to be updated in the near future.

There are anticipated changes that are expected to come into force that will impact on the assessment of dual occupancies. According to Ku-ring-gai Council’s website, the current status is:

1. Council is awaiting the gazettal by the NSW government for the minimum lot size of 1,015sqm for dual occupancy development.
2. Council is preparing controls to guide the development of dual occupancies to be included in their DCP.
3. Council is preparing a planning proposal to include a maximum floor space ratio for dual occupancies.

There is no confirmation or information available to understand the expected timeframes of these changes. However, at present, dual occupancies can only be assessed against the current applicable controls.

Where the DCP is silent and does not include controls to guide the development of dual occupancies, the controls of the Low-Rise Housing Diversity Design Guide for Development Applications should be considered. This guide helps the council to assess the DAs, until they develop their own specific controls within the DCP. In designing a dual occupancy, the controls included in this guide should also be considered. The guide can be accessed at the following link.

Low and Mid-Rise Housing

The recently introduced Low and Mid-Rise Housing Policy – SEPP (Housing) 2021 enables a greater variety of housing development across the state. Low rise development includes dual occupancies, terraces and manor houses and mid-rise development included 3 and 4 storey residential flat buildings. The policy enables Low Mid-Rise housing types within the NSW Government Local Housing Areas, which are areas within 800 meters walking distance from the edge of the mapped town centres or the entrance to a nominated train station. In Ku-ring-gai Council, the nominated town centres include:

• Roseville Station
• Lindfield Station and town centre
• Gordon Station and town centre
• Pymble Station
• St Ives Shopping Village shopping centre
• Turramurra station and town centre
• Wahroonga Station

The Low and Mid-Rise Housing Policy Indicative mapping, showing indicative LMR housing areas can be viewed at the following link.

If your lot falls within an LMR housing area, there are non-discretionary development standards which apply for dual occupancies, listed in Section 168 of the Housing SEPP. Essentially, this means that a DA lodged for a dual occupancy on this land cannot be refused on the basis of any of the following:

1. a minimum lot size of 450m2,
2. a minimum lot width at the front building line of 12m,
3. if no environmental planning instrument or development control plan that applies to the land specifies a maximum number of car parking spaces per dwelling—a minimum of 1 car parking space per dwelling,
4. a maximum floor space ratio of 0.65:1,
5. a maximum building height of 9.5m.

Despite the above mentioned non-discretionary standards, dual occupancies within the LMR areas will be assessed by council under the LEP, DCP and Low-rise Housing Diversity Design Guide for Development Applications until Council’s own controls are in force or complying development becomes available.

Dual occupancies may be subdivided by Torrens Title after an Occupation Certificate is issued.

Section 169(3) of the Housing SEPP provides the non-discretionary development standards for subdivision:

1. each resulting lot must contain no more than 1 dwelling,
2. each resulting lot must be at least 6m wide at the front building line,
3. each resulting lot must have lawful access and frontage to a public road,
4. each resulting lot must have an area of at least 225m² ,
5. each resulting lot must not be a battle-axe lot.

Subsection (4) provides that this section does not apply to strata subdivision.

Difficulties to achieving a dual occupancy

Achieving approval for a dual occupancy in Ku-ring-gai council is far from straightforward. Like all forms of development, there are site constraints that can complicate the process—and in some cases, derail it entirely. Without proper due diligence, the dream of a profitable or practical dual occupancy can quickly become unfeasible.

Topography and Drainage

The slope of the land is a major consideration in any development, and this is especially true in Ku-ring-gai, where many sites feature undulating terrain. One of the most common challenges arises when a site lacks adequate fall toward the street. In these cases, gravity-fed stormwater drainage may not be possible.

Alternative drainage solutions such as on-site absorption systems or tapping into an existing stormwater easement may need to be explored. However, securing access to an easement, particularly one that crosses a neighbour’s property, can be both time-consuming , complex and expensive. It often involves legal negotiations, detailed engineering plans, and the cooperation of adjoining landowners. Without an existing easement or the ability to establish one, lodging a dual occupancy development application may not even be viable.

Tree Preservation and Protection

Ku-ring-gai’s established character is defined by its abundant tree canopy, and as such, tree preservation is strictly enforced. Native species and mature trees, both on the subject site, neighbouring properties and on the street, are protected under local controls. Developers must take care to preserve these trees throughout the design and construction process.

In many cases, a tree root investigation may be required, especially if a new driveway or building is proposed within proximity to a protected tree. These investigations can influence the layout of a development or even prevent certain works from proceeding. Preservation of canopy cover is not just encouraged, it’s essential and enforced!

Access and Driveway Design

Providing vehiclular access to two dwellings on one lot is often more complicated than it initially appears. While utilising an existing driveway and splitting it between the dwellings is ideal, this isn’t always possible. If a new driveway is required, a number of physical and regulatory challenges may emerge.

Street trees, stormwater pits, power poles, and other existing infrastructure can all obstruct driveway placement. Relocating services such as Ausgrid power poles or stormwater pits can be extremely costly and time consuming—and only with council consent. In some cases, these obstacles alone can make a dual occupancy design unworkable.

Building on Major Roads

Sites located on major roads present another layer of complexity. Council and Transport for NSW are often more cautious with developments on busier thoroughfares due to safety concerns. To meet design standards, wider driveways may be required and vehicles must enter and exit the site in a forward direction. This can trigger the need for swept path analysis by a qualified traffic engineer, adding both cost and complexity to the design process.

Documents required for lodgement of the DA

Before submitting a development application for a dual occupancy to the local council, it is essential to ensure that all required documentation is complete and ready for submission. There are nine core documents that must accompany every new dual occupancy application (listed below). In addition to these, further documentation may be required depending on the specific circumstances of the development or unique characteristics of the site. 

Required documents

1. Architectural Plans – including a site analysis plan, site plan, floor plans, elevations, sections, shadow diagrams, schedule of colours and materials
2. BASIX Certificate
3. Landscape Plans
4. Owners Consent
5. Quantity Surveyors Report
6. Statement of Environmental Effects
7. Stormwater Plans
8. Survey Plan
9. Waste Management Plan

Additional documents

1. Arborist’s Report – if proposed works are within the canopy or drip line of protected trees under the Ku-ring-gai DCP
2. Biodiversity Development Assessment Report – if the amount of native vegetation being cleared exceeds the threshold area or the impacts of the development occur on an area mapped on the Biodiversity Values Map
3. Civil Plans – if you have a steep driveway a civil plan may be required to establish the driveway design and grades
4. Clause 4.6 Variation – if the proposed works result in a non-compliance with a development standard
5. Flood Management Plan – if land is identified as flood prone land
6. Geotechnical Report – if the proposed works result in excavation to a depth of two metres or more below the existing ground level
7. Heritage Impact Assessment – if the site is located within a heritage conservation area
8. Noise Assessment Report – for any development adjacent to a rail corridor or near a busy road
9. Subdivision plan – if Torrens title subdivision or Strata subdivision is proposed
10. Vegetation Management Plan – if the proposed works will impact either directly or indirectly on areas of remnant native vegetation or riparian areas.

For further detail, we recommend you review Ku-ring-gai Council’s Development Application Guide, accessible at the following link.

Conclusion

Ultimately, while the new planning framework creates exciting opportunities, not every property in Ku-ring-gai is suitable for a dual occupancy. Detailed feasibility assessments are essential before committing to design or purchase decisions. From drainage and access to trees and traffic, each site presents its own unique combination of constraints that must be resolved to achieve approval. Investors and homeowners considering a dual occupancy should engage experienced professionals early—planners, designers, engineers, and surveyors—to understand the full scope of site constraints and avoid costly surprises down the line.

Housing changes in NSW are creating opportunites for Ku-ring-gai Council home owners

The NSW Government’s push to increase housing supply across Sydney has resulted in dual occupancies now being permissible in Ku-ring-gai Council area, whether council likes it or not.

Whilst the Ku-ring-gai Council has traditionally been known for its strict planning controls and resistance to increasing density, these NSW planning reforms are aimed at tackling the housing crisis.

For investors, developers and home owners, this opens the door for subdivision opportunities in Ku-ring-gai and dual occupancies being the most popular option.

Can I build a dual occupancy on my land in the Ku-ring-gai Council area?

As of July 1, 2024, the NSW Government made dual occupancies permissible in R2 (Low‑Density Residential) zones across Ku‑ring‑gai—BUT only via a Development Application (DA), not a fast‑track Complying Development Certificate(CDC) route.

Quick Reminder: What is the difference between a DA and CDC?

DA allows council planners assess your design on its merits, considering things like streetscape, neighbour impacts, and local character. This can be more flexible but may be more risky as Council can refuse to grant it.

A CDC is a fast-track approval that can be issued by a private certifier or Council. If you meet every requirement exactly, you must be approved, there is no subjective decision making by council.

You can apply via DA for a dual‑occupancy in the Ku-ring-gai council area if your land:

• is R2‑zoned,
• is not heritage‑listed,
• is not fire-prone,
• is not in a TOD area (Transport-Oriented Development precincts are areas nearby a major station that the NSW Government has identified for more complex development (often mid-rise apartments, townhouses, or mixed-use buildings).
• meets future minimum lot size and width criteria once formalised (see below).

What is the minimum lot size to build a dual occupancy in Ku‑ring‑gai Council

As of mid‑2025, Ku‑ring‑gai Council endorsed a proposed minimum lot size of 1,015 sqm. Council is now waiting for the NSW Government to formalize (gazette) this requirement and reinstate the CDC pathway.

If your property is within an Local Housing Area (LHA), the state’s minimum lot size for dual occupancies is 450 m² with 12 m frontage—but currently only available under a DA.

What do I need to do if I want to build a dual occupancy with my Ku-ring-gai property

• Check your property zoning and whether it’s in an LHA or excluded (e.g., heritage, bushfire‑prone, TOD).
• Monitor updates from Ku‑ring‑gai Council or NSW Planning for formal gazettal—which is expected around mid‑2025.
• If your property meets future standards, you’ll get to choose between CDC (faster) or DA (if you fall within LHA allowances).
• Council’s Development Control Plan (DCP) and any new floor‑space ratio (FSR) provisions for dual occupancies will also be released—these may influence design details.

Get a free consultation today to find out if you qualify