HVAC Design
HVAC Design & Heat Load Calculations in Melbourne
Heat load calculations, duct design and ventilation design to AS 1668 and NCC Section J, for homes, fit-outs and commercial buildings. We work out what the building actually needs, then produce practical, installer-ready designs.
What we do
- Heat load calculations for homes and commercial spaces, room by room, so the system is sized for the building rather than guessed from floor area.
- Equipment selection: the right capacity, not just the biggest unit.
- Duct design and layouts: duct sizes, runs, outlets and return air, designed to deliver air where it's needed.
- Mechanical ventilation to AS 1668.2 for kitchens, car parks, bathrooms and enclosed spaces.
- NCC Section J energy efficiency compliance for air-conditioning and ventilation systems.
- Troubleshooting existing systems that never cool or heat evenly.
For homes
If some rooms never cool down, or your system runs flat out and still can't keep up, the answer is rarely just a bigger unit. Most problems come from duct runs that are too long, too small or crushed in the roof, or a system that was sized by floor area instead of by the house's actual heat gain: west-facing windows, insulation, ceiling heights and how the house is used.
A heat load calculation and a proper duct design fix the cause, not the symptom, and often cost far less than replacing equipment.
For builders and commercial projects
We provide HVAC and mechanical ventilation designs for new builds, extensions and fit-outs, documented for your building surveyor and installer: calculations, equipment schedules, duct layouts and compliance statements against AS 1668 and NCC Section J.
Related reading
Frequently asked questions
Why do some rooms in my house never cool down properly?
Nine times out of ten it's the ducts, not the air conditioner: ducts that are too long, too small, kinked or crushed in the roof, or leaking at the joints. We've written a full answer in our Insights section.
Is my air conditioner too small?
Maybe, but it's often sized fine and the problem is elsewhere. Oversized systems cause problems too. A proper heat load calculation tells you what the house actually needs before you spend money on a new unit.
Do I need Section J compliance?
Most new commercial and multi-residential buildings, and many extensions and fit-outs that change the air-conditioning or ventilation, need to show they meet the energy efficiency requirements of NCC Section J. Your building surveyor will confirm what applies; we provide the design and documentation.
What do you need to quote?
Floor plans and elevations if you have them, the address, and what you're trying to achieve. For an existing system that isn't working, photos of the unit, the outlets and the ductwork in the roof help a lot.