What changed in NCC 2025 for HVAC systems?

NCC 2025 tightened Section J energy-efficiency requirements by roughly 10-15%, raised minimum equipment efficiency (MEPS) for commercial cooling, heating and heat pumps, expanded commissioning requirements from initial testing to ongoing performance verification, required energy sub-metering for commercial HVAC, and updated ventilation and CO2 monitoring provisions. Performance-based verification methods are now encouraged alongside the traditional Deemed-to-Satisfy pathway.

How does NCC 2025 affect existing buildings?

Existing buildings are triggered into NCC 2025 compliance by any renovation, fit-out, or change of use that touches HVAC. Even without triggering works, existing buildings face indirect pressure through NABERS ratings, tenant ESG requirements, and lease conditions that increasingly reference NCC benchmarks. Buildings with monitoring already in place have a significant advantage in demonstrating ongoing compliance.

What are the NCC 2025 HVAC efficiency requirements?

NCC 2025 raised minimum equipment efficiency standards for commercial split systems, VRF systems, heat pumps and chillers. Requirements vary by equipment type and capacity but generally reflect a 10-15% tightening over NCC 2022. The Code also mandates separate energy metering for HVAC in commercial buildings and requires evidence of ongoing performance rather than initial compliance only.

How does HVAC monitoring help with NCC 2025 compliance?

Monitoring helps in five ways: (1) continuous performance verification for Section J, (2) ongoing commissioning evidence beyond day-one testing, (3) HVAC energy sub-metering satisfying NCC 2025 metering requirements, (4) indoor air quality tracking for updated ventilation rates, and (5) automated compliance reporting formatted for NABERS, Green Star and NCC verification. A building with 12 months of monitoring data has a stronger compliance case than one relying on design specifications.

When does NCC 2025 take effect in each state?

NSW, VIC, QLD, SA and ACT adopted NCC 2025 in line with the national timeline. WA, TAS and NT are operating under transitional arrangements with local amendments or delayed adoption. Regardless of state timeline, the direction is clear: standards are tightening, and starting monitoring now means being ahead of the compliance curve rather than scrambling to catch up after an inspection.

NCC 2025 & HVAC: What Changed and What You Need to Do

What Is the NCC and Why Should You Care?

The National Construction Code (NCC) is Australia’s primary building regulation, published by the Australian Building Codes Board (ABCB). It sets the minimum standards for safety, health, amenity, accessibility, and sustainability across every building in the country.

NCC 2025 was published in May 2025 and represents the most significant update since NCC 2022. For commercial buildings, the headline is simple: HVAC efficiency expectations just moved. If your building was compliant a year ago, it may not be now.

HVAC systems are the largest energy consumer in commercial buildings — typically 40–60% of total energy use. That makes HVAC the single biggest lever for hitting the Code’s energy-efficiency targets. Any new build, renovation, or change of use must comply with the current NCC, and non-compliance can mean failed inspections, delayed occupancy certificates, and legal liability.

Even existing buildings face pressure. NABERS ratings, tenant ESG expectations, and green-lease clauses all reference NCC benchmarks. The Code isn’t just a new-build concern anymore.

The NCC doesn’t just affect new builds. Any renovation, fit-out, or change of use triggers compliance requirements. If you’re touching the HVAC, you’re touching the NCC.

“NCC 2025 doesn’t just ask if your HVAC is efficient. It asks you to prove it — continuously.”

What Changed in NCC 2025 for HVAC

Five changes matter most for anyone designing, installing, or operating commercial HVAC.

1. Tighter Section J energy-efficiency requirements

Section J (Energy Efficiency) has been tightened by approximately 10–15% over NCC 2022. Higher minimum equipment-efficiency standards (MEPS) apply to commercial cooling and heating. Stricter envelope requirements reduce cooling loads but raise the efficiency expected of whatever HVAC serves that envelope. Most significantly, new verification methods now require actual performance data — not just design specifications. For a deeper breakdown, see our Section J Compliance Guide →

2. Enhanced commissioning requirements

NCC 2025 expands commissioning requirements beyond initial installation. There’s a new emphasis on ongoing performance verification — not just day-one testing. Systems must demonstrate they continue to operate as designed over time. This is where monitoring becomes essential. A commissioning report proves the system worked on day one. Monitoring proves it still works on day 365.

3. Improved indoor air quality standards

Ventilation rates for commercial spaces have been updated. There are new requirements for CO₂ monitoring in occupied zones, and enhanced filtration standards. The practical implication: HVAC systems must balance energy efficiency with adequate fresh-air delivery — monitoring helps optimise that trade-off without over-ventilating and wasting energy.

4. Higher minimum equipment efficiency

Commercial split systems and VRF have higher minimum COP/EER thresholds. Heat pumps have new minimum performance standards that reflect their growing role as primary heating in electrified buildings. Chillers have updated part-load efficiency requirements (IPLV). Equipment that met NCC 2022 standards may not meet NCC 2025. If you’re replacing equipment, check the new minimums before specifying.

5. Expanded metering and monitoring provisions

NCC 2025 introduces stronger provisions for energy sub-metering in commercial buildings. HVAC energy must be metered separately from lighting and other loads. This is the Code officially recognising that you can’t manage what you don’t measure.

The biggest change in NCC 2025 isn’t any single rule — it’s the shift from “design to comply” to “prove ongoing compliance”. Monitoring is no longer a nice-to-have. It’s the evidence.

NCC 2022 vs NCC 2025 — Side by Side

Requirement	NCC 2022	NCC 2025
Equipment efficiency	Minimum MEPS	Higher MEPS + performance verification
Commissioning	Initial only	Initial + ongoing performance
Energy metering	Recommended	Required (commercial HVAC)
Ventilation rates	AS 1668.2 reference	Updated rates + CO₂ monitoring
Verification methods	DTS primary	Performance-based encouraged
Section J stringency	Baseline	~10–15% tighter
Indoor air quality	Basic ventilation	Enhanced filtration + IAQ monitoring
Heat pump provisions	Limited	Expanded — recognised as primary heating

How Monitoring Helps You Comply

1. Energy-performance verification

NCC 2025 verification methods accept real performance data. Monitoring provides continuous COP, EER, and energy-consumption figures per unit. Instead of relying on manufacturer specifications, you can show certifiers the actual performance of the installed system. A building with 12 months of monitoring data has a stronger compliance case than one with a design report.

2. Commissioning evidence

Initial commissioning proves the system met spec on day one. Monitoring proves it continues to meet spec on day 365, 730, and 1,095. Automated monthly reports replace manual data collection, and building certifiers increasingly ask for ongoing performance evidence — not just the initial commissioning binder.

3. Energy sub-metering

Nexus iQ provides HVAC-specific energy metering out of the box. There’s no need for separate sub-meters — the monitoring system captures power consumption per unit. Data exports directly for compliance reporting without manual aggregation.

4. Indoor air quality tracking

Monitor CO₂, temperature, and humidity across zones. Prove that ventilation rates are maintained during occupied hours. Alert before air quality degrades — don’t wait for occupants to complain or for a certifier’s air-quality spot check.

5. Automated compliance reporting

Monthly energy-performance reports. Annual compliance summaries. Data formatted for NABERS, Green Star, and NCC verification. One data set drives every compliance framework you’re reporting into.

“The buildings that already have monitoring data will sail through NCC 2025 compliance. The ones that don’t will scramble.”

NCC 2025 compliance starts with data.

Nexus iQ generates the energy-performance evidence that building certifiers are asking for — monthly, automatically, and in a format they’ll accept.

See How It Works →

State-by-State Implementation

NCC 2025 is a national code, but state adoption timelines vary. Here’s where things stand:

State	Status	Notes
NSW	ADOPTED	Leading adoption, especially in commercial
VIC	ADOPTED	Additional state-specific requirements apply
QLD	ADOPTED	Applied to all new commercial works
WA	TRANSITIONAL	Typical 12-month transition window
SA	ADOPTED	Aligned with national timeline
TAS	TRANSITIONAL	Implementing with local amendments
ACT	ADOPTED	Aligned with NSW approach
NT	TRANSITIONAL	Delayed adoption timeline

Regardless of your state’s timeline, the direction is clear. Standards are getting tighter, not looser. Starting monitoring now means you’re ahead of the curve when NCC 2028 arrives — not scrambling to catch up.

What You Need to Do Now

Audit your current system. Check HVAC equipment against NCC 2025 minimum efficiency standards. Identify units that may not meet the new MEPS. Document current energy consumption as a baseline for any compliance conversations.
Install monitoring. Start collecting performance data now — the longer your baseline, the stronger your compliance case. HVAC-specific energy sub-metering satisfies NCC 2025 metering requirements in a single install. Continuous commissioning data proves ongoing compliance.
Plan equipment upgrades. If equipment is due for replacement in the next 2–3 years, specify to NCC 2025 standards now. Higher-efficiency equipment costs more upfront but the energy savings offset the premium. Monitoring data builds the business case.
Review ventilation. Check ventilation rates against updated NCC 2025 requirements. Consider CO₂ monitoring in high-occupancy zones. Balance ventilation with energy efficiency — don’t over-ventilate and don’t starve the space of fresh air.
Engage your building certifier. Discuss the NCC 2025 compliance pathway early. Ask what evidence they’ll accept — monitoring data is increasingly preferred. Don’t wait for an inspection to discover gaps.

The cheapest time to comply is before you’re asked to. Retrofitting compliance after a failed inspection costs 3–5× more than planning it proactively.

NCC 2025 and NABERS — The Connection

NABERS ratings and NCC compliance are increasingly linked. A building with a strong NABERS rating almost certainly meets NCC 2025 energy requirements. And because both frameworks draw from the same operational data, one monitoring investment serves two compliance purposes — one data set, two frameworks.

For more on how monitoring drives NABERS stars, see our NABERS Rating Guide →

“Think of NCC 2025 as the floor and NABERS as the ceiling. Monitoring helps you meet the floor and reach for the ceiling.”

Getting Started

Don’t wait for the inspection. Start building your compliance data now.

Book a Demo. See how Nexus iQ generates NCC 2025 compliance evidence automatically — formatted for your building certifier.
Connect your system. Nexus 32 connects to any VRF brand — Daikin, Mitsubishi, LG, Samsung, Panasonic, Fujitsu, Hitachi, Toshiba — in under a day.
Export compliance reports. Monthly energy reports are produced in a format building certifiers already accept. No manual aggregation.