Your Statement of Environmental Effects (SEE) has to prove three things about amenity: that your neighbours keep enough winter sun, that the new building does not look straight into their living rooms or private open space, and that your own dwelling gets reasonable sunlight too. Councils test this with shadow diagrams cast at 9am, 12 noon and 3pm on 21 June, window-to-window and window-to-yard distance checks, and a comparison against the numbers in their DCP. If the SEE just says “the impact is acceptable” without showing the working, expect a request for information.
Key takeaways
- Most Sydney DCPs ask that neighbouring living rooms and principal private open space keep at least 3 hours of direct sun between 9am and 3pm on 21 June, but the exact test varies by council.
- Shadow diagrams must be drawn on a survey, show existing and proposed shadows separately, and include elevational shadow diagrams where a neighbour’s windows are affected.
- Privacy is assessed by separation distance, window offsets, sill heights and screening, not by the words in the SEE.
- A good SEE quantifies the impact (hours of sun, metres of separation, area of yard in shadow) and explains how the design responds.
What the council planner is actually testing
Under section 4.15(1)(b) of the Environmental Planning and Assessment Act 1979 the consent authority must consider the likely impacts of the development on the built environment, and for houses, duplexes and townhouses amenity is the front line of that assessment. Each council sets its own amenity controls in its DCP, for example Blacktown DCP 2015, Parramatta DCP 2023, Cumberland DCP 2021 and The Hills DCP 2012, and the planner reads your SEE against them line by line.
Solar access: the 21 June test and how it is measured
The winter solstice, 21 June, is the day of the year when shadows are longest, so that is the day councils use. The typical control in Sydney reads something like this: living rooms and the principal private open space of adjoining dwellings should receive at least 3 hours of direct sunlight between 9am and 3pm on 21 June. Some DCPs test 50 per cent of the open space area, some test a nominated minimum area, and some also look at the equinox. Always confirm the wording in the current DCP for the council you are lodging with.
Where the neighbour already gets less sun than the control (common on east-west lots in Toongabbie, Guildford or Lakemba), the test usually becomes one of not making it worse. The SEE should state which situation applies.
What the shadow diagrams need to show
- Plans at 9am, 12 noon and 3pm on 21 June, at a scale that lets the planner read the neighbouring windows and yards.
- Existing shadows and proposed shadows shown separately, or hatched differently, so the additional shadow is obvious.
- Shadows drawn on a registered surveyor’s plan showing the neighbouring dwellings, their windows and their private open space, not on an aerial photo.
- Elevational shadow diagrams (shadows projected onto the neighbour’s wall) whenever a neighbouring north-facing window is affected. A plan view cannot show whether a window is in shadow.
- True north, not project north, with the source of the north point stated.
We ask for the diagrams on the same base as the site plan. When the drafting is done by our sister company ARQI they arrive in a format councils accept without follow-up questions.
Turning the diagrams into an argument
A shadow diagram on its own does not satisfy the control. The SEE has to interpret it. For each affected neighbour we write a short table or paragraph that gives the hours of sun to each living room window and to the principal open space, existing and proposed. For example: “The rear yard at the northern neighbour currently receives sun from 9am to 3pm. With the proposal it receives sun from 9am to 12:30pm, being 3.5 hours, which exceeds the 3 hour minimum in the DCP.”
Privacy: separation, offsets and sill heights
For houses and dual occupancies visual privacy carries almost all the weight. Councils look at direct sightlines from upper-level windows, balconies and decks into neighbouring habitable rooms and private open space. The tools are well established:
- Separation distance. Many DCPs treat a window-to-window distance of 9 metres or more as acceptable and expect treatment below that. The number is not universal, so check.
- Window offsets. Upper-level windows offset from the neighbour’s windows so they do not face each other.
- Sill heights. Sills at 1.5 to 1.7 metres above finished floor for bedrooms and bathrooms on the side elevations, or obscure glazing below that height.
- Screens and louvres. Fixed privacy screens to balconies, usually to a height of 1.6 to 1.8 metres, angled or with limited openings.
- Balcony placement. Rear balconies kept small and oriented to your own yard, side balconies avoided.
Your SEE should list each upper-level opening on the side and rear elevations and state how privacy is managed for it, usually as a table cross-referenced to the elevations so the planner can tick each window off.
Solar access to your own dwelling
Councils also want the new dwelling to work. Most DCPs ask that its living room and private open space receive a minimum period of sun on 21 June, often the same 3 hours. On south-facing lots this can be difficult, and the SEE should say so and explain the design response, such as a northern side courtyard or clerestory glazing. BASIX, a separate requirement under State Environmental Planning Policy (Sustainable Buildings) 2022, rewards good orientation, so the two assessments usually pull in the same direction. Our sister company NatHERS Pro prepares the BASIX certificate and we keep the orientation story consistent.
Typical controls compared
The table is indicative only. Controls are amended from time to time, so read the current DCP for the council concerned.
| Matter | Common Sydney DCP approach | What the SEE should show |
|---|---|---|
| Neighbour solar access | 3 hours of sun to living rooms and principal open space between 9am and 3pm on 21 June; some councils test a percentage of the open space area | Hours of sun existing and proposed per neighbour, with elevational shadows where windows are affected |
| Own solar access | Living area and private open space to receive sun on 21 June, often 3 hours | Orientation statement and hours of sun to living room and open space |
| Visual privacy | Separation distances, offset windows, raised sills, screening to balconies; numbers vary by council | Window-by-window table on side and rear elevations with the treatment for each |
Check the site before the drawings start
East-west lots, narrow lots under 12 metres, sloping sites where the neighbour sits lower, and corner lots are the situations where amenity decides the DA rather than being a formality. The NSW Planning Portal Spatial Viewer shows orientation, zoning and the applicable LEP, and the NSW Planning page on the Environmental Planning and Assessment Act 1979 is the starting point for the statutory framework. A quick shadow study at sketch stage costs very little and can save a redesign after lodgement.
Frequently asked questions
What time and date do shadow diagrams have to show?
9am, 12 noon and 3pm on 21 June is the standard set across NSW councils. A few councils also ask for 22 September (equinox) or 21 December. The diagrams should be based on true north and drawn on the survey.
How much sun does my neighbour have to keep?
The most common control in Sydney is 3 hours of direct sun to living room windows and to the principal private open space between 9am and 3pm on 21 June. Some councils express it as a percentage of the open space. If the neighbour already gets less than that, the test is usually that the proposal does not make it worse.
Can a privacy screen fix an overlooking problem?
Often yes, for balconies and decks, provided the screen is fixed, around 1.6 to 1.8 metres high and detailed on the plans. For windows the better fixes are offsets, raised sills or obscure glazing.
What happens if the design cannot meet the solar access control?
The SEE has to explain the departure with evidence: the site orientation, what the design has done to reduce the impact, and why the outcome is still reasonable. DCP controls are guidelines under section 4.15(3A), so a well-reasoned departure can be approved, but it has to be argued, not ignored.
Our planners prepare the amenity chapter of every Statement of Environmental Effects with the shadow and privacy working shown in full, so the council planner can see the numbers rather than take our word for it. If you have a two-storey house, duplex or townhouse design in Sydney or Western Sydney, send us the sketch plans and survey and we will provide a fee proposal for the SEE.