Window Safety Restrictions for Children in Upper Storeys

What This Requirement Covers

These requirements address the risk of people, particularly young children, falling through openable windows from upper storeys. They set minimum protections for windows where the floor beneath the opening is at a specified height above the surface beneath, and require window-restricting devices, screens or fixed barriers that limit the size of any opening and resist specified forces. The rules exist to reduce injury and fatality risk from accidental falls and to provide a consistent, enforceable standard for designers, builders and certifiers across buildings covered by the National Construction Code (NCC) and the ABCB Housing Provisions.

The provisions apply to sleeping rooms and selected other room types in multi-occupancy and specialised buildings (including bedrooms in Class 2 and 3 buildings, Class 4 parts of buildings, and Class 9b early childhood centres), and to residential housing in Volume Two where the ABCB Housing Provisions apply. They are written so that windows, screens, restricting devices and barriers must meet dimensional and load resistance criteria and include child-resistant release requirements where relevant.

Key Requirements

1. Applicability trigger - 2 m: A window opening must be provided with protection where the floor below the window is 2 m or more above the surface beneath, in a bedroom in a Class 2 or 3 building or Class 4 part, or in a Class 9b early childhood centre (see NCC Volume One, Clause D3D29 [2019: D2.24] and ABCB Housing Provisions 11.3.7 and 11.3.8).
2. Minimum protection where lowest opening < 1.7 m: If the lowest level of the window opening is less than 1.7 m above the floor, the openable portion must be protected by either:
3. a device capable of restricting the window opening; or
4. a screen with secure fittings.
5. 125 mm sphere criterion: Any device, screen or barrier protecting the opening must not permit a 125 mm sphere to pass through the window opening or screen (NCC Volume One, Clause D3D29(2)
   2. (i) and ABCB Housing Provisions 11.3.7(2)(b)(i)).
   3. 250 N horizontal load requirement: The restraining device or screen must resist an outward horizontal action of 250 N applied against the window restrained by a device or the screen protecting the opening (NCC Volume One, Clause D3D29(2)(b)
   4. and ABCB Housing Provisions 11.3.7(2)(b)(ii)).
   5. Child-resistant release mechanism: If the screen or restricting device can be removed, unlocked or overridden, it must include a child resistant release mechanism (NCC Volume One, Clause D3D29(2)(b)
   6. and ABCB Housing Provisions 11.3.7(2)(b)(iii)).
6. Barrier requirement - 865 mm: A barrier with a height not less than 865 mm above the floor is required to an openable window in addition to window protection where a child resistant release mechanism is required, and where the floor below the window is 4 m or more above the surface beneath if the window is not otherwise covered by the 2 m bedroom/opening rules (NCC Volume One, Clause D3D29(3)).
7. Barrier anti-climb and sphere limits: A barrier required by the provisions must not permit a 125 mm sphere to pass through it and must not have any horizontal or near-horizontal elements between 150 mm and 760 mm above the floor that facilitate climbing (NCC Volume One, Clause D3D29(4)).
8. Special areas excluded from some barrier rules: For openable windows in fire-isolated stairways, fire-isolated ramps and other emergency-use areas, and in Class 7 (other than carparks) and Class 8 buildings, certain barrier requirements in D3D29(3) to (5) may not apply (NCC Volume One, Clause D3D29(5)).
9. Relevant NCC and Housing Provisions references:
10. NCC 2022 Volume One - Clause D3D29 (Protection of openable windows) [2019: D2.24].
11. ABCB Housing Provisions Standard 2022 - Sections 11.3.7 (Protection of openable windows - bedrooms) and 11.3.8 (Protection of openable windows - rooms other than bedrooms), including explanatory information.
12. Australian Standards: While window safety provisions above are specified in the NCC and Housing Provisions, relevant Australian Standards that may apply to selection, installation and performance include AS 2047 (Windows in buildings - selection and installation), AS 1288 (Glazing - selection and installation), and standards covering screens and hardware performance where applicable. Designers should reference these standards for glazing, framing and hardware compliance in accordance with the NCC.

Residential vs Commercial

1. Residential (Class 1 and 10 and typical detached housing under Volume Two / ABCB Housing Provisions): The ABCB Housing Provisions (Volume Two) set out the specific window protection requirements for bedrooms and other rooms when the drop beneath is 2 m or more. The Housing Provisions mirror the intent and criteria (125 mm sphere, 250 N load, 865 mm barrier where required) and provide guidance and deemed-to-satisfy solutions for houses, townhouses and other housing typologies (see ABCB Housing Provisions 11.3.7 and 11.3.8).
2. Multi-residential and commercial-type buildings (Class 2, 3, 4 parts, and certain Class 9 uses): NCC Volume One applies. Bedrooms in Class 2 and 3 buildings and Class 4 parts must be protected where the floor below the window is 2 m or more above the surface beneath (NCC Volume One, Clause D3D29). Class 9b early childhood centres are explicitly included and have equivalent protections due to the presence of young children. Higher-risk or specialised commercial classes (Class 5-9) do not generally use the Housing Provisions but may have relevant requirements in Volume One or in specific class requirements; designers should apply the NCC Volume One clauses and any state schedules that modify them.

Exceptions and Exemptions

1. Where the lowest level of the openable portion of a window is at least 1.7 m above the floor, no additional window restricting device or screen is required for the 1.7 m rule (ABCB Housing Provisions explanatory information to 11.3.7).
2. A restricting device or screen that is securely fixed (for example, pop-riveted so it cannot be unlocked, removed or overridden without tools such as a drill) and thereby not a child-resistant release mechanism can be treated as a permanent fixture; in that case the 865 mm barrier may not be required (ABCB Housing Provisions explanatory information to 11.3.7). The fixings must still allow for emergency egress or fire safety considerations if necessary.
3. Situations where the window is within a fire-isolated stairway, fire-isolated ramp or other areas used primarily for emergency purposes may be excluded from some barrier requirements (NCC Volume One, Clause D3D29(5)).
4. Performance solutions: The NCC allows for Performance Solutions where an alternative means can be demonstrated to achieve the required level of safety (see NCC assessment methods). Where a deemed-to-satisfy solution is not used, a Performance Solution must reference appropriate evidence, testing or risk assessment.

State and Territory Variations

1. The NCC is national, but each state and territory may adopt schedules that modify or add to national provisions. Designers must check the relevant state schedule (Schedules 4-12 in NCC Volume One) for jurisdictional variations or added requirements. For example:
2. Queensland, New South Wales, Victoria, Western Australia, South Australia, Tasmania, Northern Territory and the ACT each maintain their own state or territory variations or interpretations that can affect specific applications of NCC provisions. Always verify against the state schedule in NCC 2022 Volume One (Schedules 4-12) for the project jurisdiction.
3. Local council planning overlays or state regulations may also impose additional child safety or window guarding requirements in certain building types (for example, early childhood centres or health care premises). Always confirm with the relevant building consent authority or registered certifier.

Practical Compliance Tips

1. Ensure you check the floor-to-surface distance beneath any window: the 2 m trigger and the 4 m trigger for some barrier rules are critical thresholds - measure and record these dimensions on drawings and site checklists.
2. Design openable windows so the lowest point of the openable portion is at or above 1.7 m where possible to avoid additional restricting devices or barriers.
3. If using restricting devices or screens, specify products tested or rated to not allow a 125 mm sphere and to resist 250 N outward horizontal force. Keep manufacturer test certificates or evidence on file for certifier inspection.
4. When a removable screen or device is proposed, select a child-resistant release mechanism that still allows for safe egress in an emergency. Clearly document how the mechanism operates and include instructions and labeling for occupants.
5. Avoid barrier designs with horizontal or near-horizontal elements between 150 mm and 760 mm above the floor to reduce climbability; specify vertical balustrade elements or compliant infill patterns instead.
6. If relying on permanently fixed screens or hardware to avoid the 865 mm barrier, ensure the attachment method is durable and not readily overridden. Document fastening methods and provide maintenance guidance.
7. Check the relevant Australian Standards for glazing, framing and hardware (AS 2047, AS 1288, AS 2208 where applicable) in addition to the NCC/Housing Provisions, and confirm any state schedule modifications before issuing drawings or commencing work.

References

1. NCC 2022 Volume One - Clause D3D29 (Protection of openable windows) [2019: D2.24]
2. ABCB Housing Provisions Standard 2022 - Sections 11.3.7 and 11.3.8 (Protection of openable windows)
3. AS 2047 (Windows in buildings - selection and installation), AS 1288 (Glass in buildings - selection and installation), and related glazing standards

Could not determine: false