2 Ducted Systems - 1 Roof

In this video, the Chillin team takes you through a Queensland home where two separate ducted air conditioning systems needed to be installed for independent comfort - one for each section of the home, divided by an internal wall. Same roof, same visit, two completely independent systems.

What Happens Before the Ceiling Is Closed?

Early ducted air conditioning work happens before the ceiling is closed. At this stage, our team installs the indoor unit, runs the ductwork, positions the air outlets and return air grilles, and routes the refrigerant and drain lines ready for final connection.

Getting this early work right is critical - once the ceiling is sealed, correcting mistakes is costly and disruptive. That's why we put so much emphasis on planning before a single piece of duct goes in.

Two Independent Systems, One Build

Installing two ducted systems in the same build is common on larger homes or dual-living layouts where each section needs its own independent climate control. In this case, an internal wall divides the home into two separate areas — each with its own indoor unit, its own ductwork, and its own outdoor compressor.

While the roof structure is shared, the two systems operate completely independently of each other. Each one was designed, sized, and installed to serve only its own section — so the owners of each space have full control without any interaction between the two.

Key Steps Covered in the Video

• ●Positioning each indoor unit for optimal duct runs and future service access
• ●Running flexible ductwork to each outlet while maintaining minimum bend radii
• ●Sizing return air plenums correctly for each system's airflow requirements
• ●Routing refrigerant lines and drain lines independently for each system
• ●Keeping both installations clean and clearly labelled for final setup

Why Airflow Design Matters

Ducted systems are only as good as their ductwork design. Undersized ducts create excessive static pressure, which reduces airflow, increases noise, and puts additional load on the compressor. Oversized ducts waste material and can cause uneven temperature distribution across zones.

For each system in this job, we calculated the total duct equivalent length and confirmed outlet sizes matched the unit's airflow specifications — keeping everything within manufacturer tolerances and Australian industry guidelines.