is a duplex a class 2 building?
Yes, a duplex is typically classified as a Class 2 building under the National Construction Code (NCC) of Australia when it contains two separate residential units under one roof sharing a common wall. However, there's an important distinction:
Stacked Duplexes (One Above Another)
Classified as Class 2 buildings
Contains 2 separate dwellings with one above the other
Typically shares a horizontal dividing floor/ceiling
2. Side-by-Side Duplexes
Can be classified as Class 1a buildings
Two dwellings side by side with a fire-rated common wall
Each dwelling has its own direct access to outside
Key points:
The classification impacts building requirements, particularly fire safety measures
Class 2 buildings have more stringent requirements than Class 1a
The specific classification can affect construction costs and compliance requirements
It's important to confirm the exact classification with your building certifier or council as it will affect:
Fire separation requirements
Sound insulation requirements
Energy efficiency provisions
Access requirements
Building services requirements
This classification distinction can significantly impact your project's design, costs, and approval process.