NCC 2022 and NCC 2025 in South Australia
What applies now, what changes in May 2027, and how ventilation, airtightness and condensation management fit together.
By Jonathen Hindry · Published 21 June 2026 · Updated 11 September 2026 · 12 min read
Who this is for: builders, designers, building certifiers and homeowners working on new homes and renovations in South Australia. This guide explains the current NCC 2022 position, the confirmed NCC 2025 timetable and the practical relationship between ventilation, airtightness and condensation management. It is general guidance, not a substitute for a project-specific assessment by your certifier.
South Australian update — 5 September 2026
South Australia will adopt the Building Code provisions of NCC 2025 on 1 May 2027. Until 30 April 2027, NCC 2022 Amendment 2 remains the applicable Building Code. The NCC 2025 Plumbing Code has applied in South Australia since 1 May 2026.
Start with the applicable code and pathway
Ventilation, energy efficiency and building-envelope sealing appear in different parts of NCC Volume Two. They should not be collapsed into a universal “5 ACH50 rule”. NCC 2022 H6V3 uses an air-permeability threshold within an optional Verification Method; Part 10.6 addresses ventilation to rooms; and Part 10.8 addresses condensation management.
For South Australian projects there is a second thing to get right: the dates. SA adopted most of NCC 2022 on 1 May 2023, but deliberately deferred the “modern homes” package — the 7-star energy provisions, livable housing design and the improved condensation management measures — to 1 October 2024. If you read a generic national summary that says “1 May 2023”, it does not describe when the condensation and energy rules actually started for SA homes.
The South Australian timeline
NCC 2022 general adoption in SA
South Australia adopted the bulk of NCC 2022 — but the energy efficiency, livable housing and improved condensation management measures were held back for a later start date.
Modern homes provisions commence
The 7-star-equivalent thermal performance target, whole-of-home energy budget, livable housing design and improved condensation management measures commenced for most new Class 1 and Class 2 homes, subject to South Australian concessions.
NCC 2022 Amendment 2
NCC 2022 Amendment 2 became the current amendment. In South Australia it must be read with the state variations, Ministerial Building Standards and transitional arrangements that apply to the project.
NCC 2025 Plumbing Code
South Australia adopted the Plumbing Code within NCC 2025. This did not change the Building Code applying to building work.
NCC 2025 Building Code
South Australia will adopt the Building Code provisions of NCC 2025. NCC 2022 Amendment 2 remains in force until 30 April 2027.
Alterations & additions to existing homes
The current concession delays the modern-homes provisions for alterations and additions to existing Class 1 homes until this date. The relevant NCC 2019 Amendment 1 provisions remain available in the interim where the concession applies.
Concessions: SA approved transitional concessions for small and irregular allotments, worker and tourist accommodation, the Mount Barker Master Planned Neighbourhood Zone, and off-site manufactured homes of 70 m² or less. Some of these may follow NCC 2019 (6-star) thermal performance while still meeting the NCC 2022 energy-usage and condensation management requirements. Always confirm the pathway that applies to your specific allotment and class of work with your certifier.
The provisions to keep separate
Building-envelope sealing verification
Verification MethodWhat it requires
H6V3 is an optional Verification Method. Where it is used and air permeability is verified at not more than 5 m³/(h·m²) at 50 Pa, a mechanical ventilation system must be provided in accordance with H6V3.
The formula
For continuous operation: Q (L/s) = 0.05 × Floor Area (m²) + 3.5 × (Number of Bedrooms + 1). The full H6V3 formula includes a time fraction for intermittent operation.
Use the right unit
Air permeability in m³/(h·m²) and air changes per hour at 50 Pa (ACH50) are different measurements. They must not be used interchangeably in specifications, quotes or reports.
Ventilation to rooms
VentilationDeemed-to-Satisfy provisions
Part 10.6 of the ABCB Housing Provisions sets out natural-ventilation provisions for rooms. Mechanical ventilation may be used through the applicable NCC pathway, including H4D7 and AS 1668.2 where relevant.
Project-specific design
A home's ventilation solution depends on its selected compliance pathway, building design and measured or specified envelope performance. The NCC does not prescribe MVHR for every home.
Condensation management — exhaust & vapour
CondensationExhaust direct to outdoor air
Exhaust from a kitchen, range hood, bathroom, sanitary compartment or laundry must discharge directly — or via a shaft or duct — to outdoor air. Venting into a roof cavity, sub-floor or wall cavity is explicitly non-compliant. This closes one of the most common and damaging installation defects in Australian housing.
Wet-area run-on interlock
A non-continuous exhaust fan serving a bathroom or sanitary compartment that has no natural ventilation (no operable window to outside) must be interlocked with the light switch and run on for a minimum of 10 minutes after the light is switched off, ensuring post-shower moisture is cleared.
Vapour permeance by climate zone
Pliable building membranes are now classified by climate zone. In Climate Zones 4 and 5 — which includes Adelaide — wall membranes must be vapour permeable to at least Class 3, or another compliant pathway used. The Adelaide Hills and South East (Climate Zone 6) carry more stringent requirements, including roof space ventilation.
For a deeper treatment of the ventilation clause and the condensation exhaust rules on their own, see our NCC 2022 ventilation requirements explainer.
Airtightness targets are still useful
ACH50 remains a useful way to describe and compare whole-building airtightness. It is measured with a blower door test, but it is not the same unit as the m³/(h·m²) air-permeability result used by H6V3. These performance benchmarks are not universal NCC pass-or-fail lines:
A 7-star rating does not automatically establish a particular blower door result. Set the airtightness target deliberately, coordinate the ventilation strategy around it and verify the completed envelope when the project pathway or performance brief requires it. For more on what ACH50 measures, see Airtightness Explained.
Common pathways to coordinate
Deemed-to-Satisfy (DTS)
- Apply the relevant prescriptive ventilation provisions in Part 10.6.
- Provide compliant exhaust (direct to outside) and the wet-area run-on interlock.
- Use a climate-zone-compliant vapour-permeable wall membrane.
Verification or Performance Solution
- Use H6V3 when the project nominates the building-envelope sealing Verification Method and meet its testing and ventilation conditions.
- For a Performance Solution, demonstrate compliance with the relevant Performance Requirements using appropriate evidence.
- Coordinate the energy assessment, airtightness target, ventilation design, testing and certifier requirements from the outset.
Where MVHR and blower door testing fit
A properly designed and commissioned MVHR system can form part of a compliant ventilation solution, while a blower door test provides measured evidence of envelope performance. Neither automatically establishes whole-project NCC compliance:
Ventilation design
MVHR airflows, controls and operation must be coordinated with the project's selected NCC pathway and actual building.
Kitchen extraction
General MVHR kitchen extract does not replace a compliant rangehood strategy. Rangehood discharge and make-up air need separate coordination.
Part 10.8 — continuous wet-area extraction
MVHR runs 24/7, keeping wet areas in slight negative pressure and clearing moisture far more reliably than an intermittent fan.
7-star energy target
Heat recovery returns warmth from the exhaust air to the incoming fresh air, so the required ventilation doesn't undo the thermal performance you designed for.
Evidence of airtightness
A blower door test documents the achieved result for H6V3, a NatHERS airtightness credit, Passive House certification or a project performance target, as applicable.
Defect risk
Testing mid-build locates leaks while they can still be sealed — before plasterboard buries them — reducing condensation and callback risk.
What changes with NCC 2025?
NCC 2025 includes updated residential condensation-management provisions in Volume One Part F8 and the Housing Provisions Part 10.8, including changes affecting wall and roof assemblies. It does not introduce a further increase in residential energy-efficiency stringency: the NCC 2022 residential requirements continue.
The South Australian Government has advised that further implementation detail will be provided before adoption. Until 30 April 2027, project documentation should continue to identify NCC 2022 Amendment 2 as the current Building Code rather than treating NCC 2025 as already mandatory for building work.
A note on SA climate zones
The condensation management requirements — particularly vapour permeance of wall membranes and roof space ventilation — vary by NCC climate zone. Adelaide and most of the coastal plain sit in Climate Zone 5 (warm temperate). The Adelaide Hills, Mount Lofty Ranges and the South East around Mount Gambier fall into Climate Zone 6 (mild temperate), which carries more stringent condensation requirements. Northern and outback SA sit in the hotter, drier Zones 3 and 4. Confirm the climate zone for your exact site, because it changes the compliant membrane class and roof ventilation detailing.
Should you blower door test in SA?
NCC 2022 does not force every home to be tested under every pathway. Testing is required when the project relies on a measured result, including H6V3, a NatHERS airtightness credit or Passive House certification. A mid-construction test catches leaks while they remain accessible; a completion test documents the achieved result for the project record.
Our blower door testing service →Frequently asked questions
When will NCC 2025 apply to building work in South Australia?
South Australia will adopt the NCC 2025 Building Code on 1 May 2027. NCC 2022 Amendment 2 remains the applicable Building Code until 30 April 2027.
What is the H6V3 ventilation threshold in NCC 2022?
H6V3 is an optional Verification Method for building-envelope sealing. Where it is used and verified air permeability is not more than 5 m³/(h·m²) at 50 Pa, mechanical ventilation must be provided in accordance with H6V3. This air-permeability unit is not the same as ACH50.
What is the NCC 2022 mechanical ventilation formula?
The minimum continuous mechanical ventilation airflow for a dwelling is calculated as: Airflow (L/s) = 0.05 × Floor Area (m²) + 3.5 × (Number of Bedrooms + 1). For example, a 220 m² four-bedroom home requires 0.05 × 220 + 3.5 × 5 = 11 + 17.5 = 28.5 L/s. Systems must be installed in accordance with AS 1668.2.
Does NCC 2022 require a blower door test in South Australia?
Not for every home. Testing is required when a project relies on a measured airtightness result under its nominated pathway, including H6V3, a NatHERS airtightness credit or Passive House certification. Many projects also test voluntarily to verify performance and find leakage defects while they remain accessible.
Does MVHR automatically satisfy NCC 2022 in South Australia?
No. A correctly designed and commissioned MVHR system can form part of a compliant ventilation solution, but compliance depends on the nominated NCC pathway, airflow, controls, exhaust and project-specific requirements. General MVHR kitchen extract also does not replace a compliant rangehood strategy.
Are alterations and additions required to meet the new-home provisions?
Not automatically. South Australia's current concession delays the modern-homes provisions for alterations and additions to existing Class 1 homes until 1 May 2030. The pathway still depends on the work, application date and applicable Building Rules and should be confirmed with the project certifier.
What vapour permeance does a wall membrane need in Adelaide?
Adelaide is in NCC Climate Zone 5. In Climate Zones 4 and 5, a pliable building membrane used on the outside of the wall must be vapour permeable — a minimum of Class 3 vapour permeance — or another compliant condensation-management pathway must be used. The cooler Adelaide Hills and South East (Mount Gambier) fall into Climate Zone 6, which has more stringent condensation management requirements, including roof space ventilation.
Official sources
Working on a South Australian project?
HiPer Haus works with homeowners, builders and designers from early design through installation, testing and commissioning. Talk to us about condensation risk, ventilation, airtightness and a practical pathway for your project.
Written by
Jonathen HindryFounder of HiPer Haus. ATTMA Level 1 Airtightness Tester, Certified Passive House Tradesperson and 25+ year plumber — blower door testing, MVHR design and heat pump hot water across Adelaide and South Australia.
