Design the system around the home — not the fan
A well-designed system puts fresh air where people need it, extracts moisture and pollutants where they are created, and keeps ductwork and equipment practical. It also considers how the home will behave through the seasons — including summer heat and winter moisture.
Understand the layout
Review room locations, doors, service areas, ceiling spaces and available installation routes.
Plan the airflow
Consider which spaces need fresh-air supply, which need extraction, and how air can move through the home.
Choose the system
Match the ventilation approach and equipment to the building, occupancy, requirements and practical constraints.
What we look at in a ventilation design
The design should make sense on the drawing before anyone starts installing ductwork. We look at the whole home, not just the fan.
- Room use and occupancy
- Bathrooms, kitchens, laundries and other moisture sources
- Supply and extraction locations
- Equipment location and access
- Ceiling space and duct routes
- Practical airflow paths through the home
From plans to a practical ventilation approach
Ventilation is about more than moisture. We also consider airflow, comfort and how the home can respond to summer heat.
Provide the floor plans and project information available.
Consider room use, moisture sources, airflow and installation constraints.
Plan the equipment, supply and extraction points and airflow paths.
Use the design information to support the wider building and installation process.
What to send EVOAQ
Not sure if your plans are ready? Send us what you have — even rough sketches — and we will tell you if we have enough to get started.
- Floor plans and room names or intended use
- Ceiling heights where known
- Bathrooms, kitchens, laundries and other service areas
- Preferred equipment or system type, if selected
- Plant-room, ceiling-access or duct-route constraints
- Project location and build stage
Which EVOAQ solution?
Whole-home ventilation — for fresh-air supply and overall IAQ.
Dedicated extraction — for bathrooms and other moisture or pollutant sources.
Decentralised ventilation — when room-by-room control and shorter duct runs make sense.
Heat transfer — when moving existing heat between rooms is part of the brief.
Not sure which ventilation approach suits your build? Compare the options →
Good design prevents expensive compromises
Avoid overheating
Plan supply and extraction locations so the system supports useful summer heat purging rather than simply moving unwanted heat around the home.
Control moisture at the source
Put extraction where moisture and pollutants are created, while keeping the wider airflow strategy working for the home.
Future-proof the installation
Good planning means practical duct routes, suitable equipment locations and quieter, more efficient operation.
Ventilation Design FAQs
Why can't the builder just work out the ventilation during installation?
They can install a system, but design decisions made late can create compromises. Planning early helps coordinate airflow, duct routes, equipment locations and service areas before other building work gets in the way.
Can ventilation design help with summer overheating?
Yes. Ventilation design should consider summer as well as winter. Supply and extraction locations can be planned to support effective air movement and heat purging when outdoor conditions are suitable. EVOAQ systems now include Summer Mode to help purge accumulated hot air from the home.
Read: Why NZ homes overheat — and why ventilation alone won't save you →
Do I need positive pressure, balanced ventilation or decentralised extraction?
There is no single system that suits every building. The right approach depends on the building, occupancy, moisture sources, airtightness, layout and project requirements. Our design process starts with the home rather than assuming a particular system.
My house is already built. Is it too late for ventilation design?
No. Existing homes can still be assessed. The design simply needs to account for the building as it exists, including available ceiling space, access, existing services and practical duct routes.
Can EVOAQ help with Building Consent information?
Yes. We provide project-specific ventilation design information to support the consent process and coordinate with the designer, builder or consenting authority where required.
Have a project ready to plan?
Send EVOAQ your plans and project information and we can discuss the ventilation approach before installation.
Submit Your Plans