Energy Efficiency / 7-Star
Since NCC 2022, new homes must achieve 7-star NatHERS plus a whole-of-home energy use budget. Building fabric, glazing and services all in scope.
Overview
Section 13 sets the energy efficiency provisions for Class 1 and 10 buildings. The deemed-to-satisfy pathway requires insulation R-values, glazing performance, sealing, and services to all meet specified minimums. The performance pathway is via NatHERS modelling — 7 stars for the building fabric, plus a whole-of-home energy use cap covering hot water, HVAC, lighting and pool/spa.
Key Clauses to expand
- Part 13.2 — Building fabric (roof, walls, floors, insulation R-values per AS/NZS 4859)
- Part 13.3 — External glazing (U-value, SHGC, glazing calculator)
- Part 13.4 — Building sealing
- Part 13.5 — Services (HVAC, hot water per AS/NZS 2712, lighting; ducts to AS 4254)
- Part 13.6 — Heating and cooling loads
- Part 13.7 — Energy usage
On-site Checklist to expand
- NatHERS rating ≥ 7 stars
- Whole-of-home score within budget for climate zone
- Roof, wall and floor insulation per climate zone schedule
- Glazing U-value/SHGC matched to design (and supply order)
- Thermal breaks on metal-framed construction
- Sealing of penetrations, exhaust fans with self-closing dampers
Common Gotchas to expand
- Designed for 7 stars, built with downgraded glazing — fails compliance
- Insulation compressed or missing in cathedral roofs
- Thermal bridging through steel framing
- Exhaust fans without self-closing dampers leak conditioned air
- Downlights penetrating insulation reduce effective R-value
Notes & Examples to fill in
Add worked examples, diagrams, photos and project-specific notes here as you accumulate them.