NCC 2022 Volume 1 — Existing Buildings (Part A2 / Schedule 4)
National Construction Code Volume 1 — Performance Solution Pathway for Existing Buildings
The National Construction Code (NCC) Volume 1, published by the Australian Building Codes Board (ABCB), is the deemed-to-satisfy and performance-based building code for Class 2 to Class 9 buildings (multi-residential, commercial, assembly, healthcare and storage) in Australia. The NCC defines Performance Requirements (the mandatory outcomes that must be achieved), Deemed-to-Satisfy Provisions (prescriptive solutions that demonstrably comply with the Performance Requirements), and the Performance Solution pathway (where compliance is demonstrated through engineered alternatives that achieve the Performance Requirement without following the prescriptive deemed-to-satisfy). For existing buildings, the NCC Performance Solution pathway is particularly relevant — Section A2 of NCC Volume 1 (Compliance with Performance Requirements) and Schedule 4 (Performance Solutions framework) provide the basis for engineered compliance where deemed-to-satisfy provisions cannot be directly applied (typical of heritage buildings, adaptive-reuse projects, and continuing-life recertifications). The NCC is updated on a triennial cycle (NCC 2019, NCC 2022, NCC 2025); the controlling edition for a project is determined by the date of the building approval. The structural Performance Requirements (B1.0 to B1.5 in NCC Volume 1) cover stability, serviceability, durability and fire resistance, and reference Australian Standards (AS 3600, AS 3700, AS 4100, AS 1170 series, AS 5100 series) as the deemed-to-satisfy means of compliance.
The NCC Performance Solution pathway is the regulatory framework that makes existing-asset structural certification possible. For pre-NCC (or pre-NCC-current-edition) buildings, the structural deemed-to-satisfy provisions cannot be directly applied — the building was not designed to current standards, current durability cover, or current importance-level mapping, and asking it to retroactively comply with current deemed-to-satisfy is not a meaningful test. The Performance Solution pathway is the alternative compliance route that allows engineered demonstration of equivalent performance against the underlying Performance Requirement (typically B1.1 — structural reliability against ultimate failure, B1.2 — serviceability, B1.3 — fire resistance), with the engineering documentation supporting the Performance Solution becoming the basis for Form 15 RPEQ certification and Form 12 building-certifier classification. Three application points matter for TRSC's existing-asset practice. First, the Performance Solution must explicitly identify the Performance Requirement being addressed and the engineering evidence demonstrating equivalent performance. TRSC's Performance Solution engineering reports include the relevant Performance Requirement statement, the deemed-to-satisfy provision that cannot be applied (with the reason — typically heritage retention, structural-incompatibility, or impracticability of retrofit), the engineered alternative, the calculation and analysis demonstrating equivalence, and the engineering judgement applied. The Victory Hotel post-fire reconstruction used a Performance Solution under NCC B1.3 (fire resistance) — the existing 1855 colonial masonry could not retroactively comply with current AS 3700 deemed-to-satisfy fire-resistance provisions, but the engineering evidence (combined with documented heritage protection and operational fire-safety measures) demonstrated equivalent performance against the Performance Requirement. Second, Performance Solutions for structural matters require building-certifier acceptance under the NCC Schedule 4 framework, with the certifier reviewing the engineering documentation as part of their Form 12 decision. TRSC's protocol on heritage and adaptive-reuse projects is to engage the building certifier from project inception, identifying which deemed-to-satisfy provisions cannot be directly applied and developing the Performance Solution methodology collaboratively. The certifier's Form 12 then references the Performance Solution as the basis for the classification decision, with the supporting engineering documentation retained in the project file. Third, Performance Solutions for existing buildings must address durability and continuing-life as well as immediate compliance. AS 3600 deemed-to-satisfy durability cover is calibrated to a 50-year design life under specified exposure; existing concrete with measured cover below the deemed-to-satisfy minimum cannot retroactively comply, but a Performance Solution demonstrating measured-property residual durability against a defined remaining life can establish equivalent performance. TRSC's residual-life calculations for heritage and aged commercial buildings typically follow this Performance Solution structure, with the AS/NZS ISO 31000 risk-classification matrix establishing the engineering basis for the residual-life conclusion. The 12 Creek Street facade investigation, the 140 William Street curtain-wall assessment and several Brisbane CBD heritage continuing-life recertifications have used this Performance Solution methodology with documented building-certifier acceptance.
Form 15 RPEQ certifications for existing-asset structural adequacy where deemed-to-satisfy provisions cannot be directly applied reference NCC Performance Requirements (typically B1.1, B1.2 and B1.3) as the compliance basis, with the Performance Solution engineering documentation supporting the certification. The Form 15 file documents the relevant Performance Requirement, the deemed-to-satisfy provision that cannot be applied and why, the engineered alternative and the engineering evidence of equivalent performance, and the building-certifier acceptance of the Performance Solution under NCC Schedule 4 framework. For continuing-life recertifications, the Performance Solution residual-life calculation is retained in the file with explicit AS/NZS ISO 31000 risk-classification supporting the conclusion. The Performance Solution Form 15 is regulatorially distinct from a deemed-to-satisfy Form 15 — both are valid under the Building Regulation 2021 (Qld) framework, but the supporting documentation requirements differ.