NCC Version:
2022, Volume 1
Area of NCC Requirements:
D3D14 – Stairway goings and risers
D3D22 – Handrail requirements
D4D3 – Access to buildings via accessible entry points
D4D4 – Compliance of ramps and stairways with AS1428.1
F5D2 – Minimum ceiling height requirements
Problem:
Several areas of the proposed development deviated from the NCC’s Deemed-to-Satisfy (DTS) provisions. Issues include: use of secondary entries as accessible entries, non-compliant handrail terminations, stair design deviations, limited ceiling height at roof hatches, and a top riser step height exceeding the standard. These departures affect access, safety, and usability, especially for people with a disability, and require a performance-based approach to demonstrate compliance with NCC performance requirements.
Solution:
The report provides five performance solutions supported by expert judgement and comparative analysis with the DTS provisions. These solutions include the provision of alternate accessible routes, justification for 90-degree handrail turns and single handrails in staff-only areas, vertical handrail sections in fire stairs, and limited head height at roof hatches within sole-occupancy units. Each solution demonstrates that the proposed design meets the intent of the NCC, ensuring access that is safe, equitable, and dignified given the nature and use of each space.
Finalised Report:
The performance-based design report, concludes that all identified compliance departures satisfy the relevant Performance Requirements (D1P1, D1P2, F5P1) of the NCC 2022. Enhanced signage and construction detailing have been recommended to support implementation. The assessment confirms that, despite deviations from DTS provisions, the building achieves acceptable standards for access and safety based on usage, context, and expected occupant profiles.