When it comes to reducing humidity and preventing mould, one size doesn’t fit all. Choosing the right dehumidifier for your home can make the difference between a fresh, healthy indoor space — or one that still feels damp, musty, and uncomfortable.
Whether you’re tackling winter condensation in Melbourne or year-round moisture in the tropics, this guide will help you pick the best dehumidifier size based on your room and environment.
Why dehumidifier size matters
Dehumidifier size is measured in litres per day (L/day) — referring to how much moisture the unit can remove from the air in 24 hours. Choose one that’s too small and you may barely notice a difference. Too big, and you might waste energy and space.
The more humid and damp a room is, the more powerful your dehumidifier should be.
But size isn’t the only factor. Room conditions, insulation, and usage also play a role in how effective a dehumidifier is — especially in Australia’s diverse climates.
Room-by-room dehumidifier guide
Here’s how to choose the right capacity for different parts of your home:
🛏️ Bedrooms (10–20 sqm)
Recommended size: 7–12L/day
Bedrooms don’t typically have major moisture issues, but they still benefit from humidity control — especially if you live with asthma, allergies, or pets.
Features to look out for:
- Low noise levels
- Sleep mode
- Air filter options for better air
Recommended dehumidifier:
🚿 Bathrooms & Laundries (small, enclosed spaces)
Recommended size: 6–12L/day
These rooms are hotspots for mould, especially in winter. A compact dehumidifier with continuous drainage is ideal.
Features to look for:
- Compact footprint
- Hose drainage
- Auto shut-off
Recommended dehumidifiers:
- Ionmax ION610
- Ionmax ION622
🛋️ Living Rooms (20–40 sqm)
Recommended size: 10–18L/day
These larger, open spaces often require a more powerful unit — especially if the area is shared with a kitchen or pets.
Features to look for:
- Timer function
- Child lock
- Filter change alerts
Recommended dehumidifiers:
🏠 Open-plan & large areas (40–80+ sqm)
Recommended size: 18–25L/day
In open-plan homes, a high-capacity dehumidifier ensures even, consistent humidity control.
Features to look for:
- Strong airflow
- Large water tank or continuous drainage
- HEPA filter (optional)
Recommended dehumidifiers:
🧰 Garages, basements & storage rooms
Recommended size: 12–18L/day (or higher depending on space)
These areas are prone to condensation, rust, and mildew — especially in colder months.
Features to look for:
- Desiccant technology (works better in low temps)
- Hose drainage
Recommended dehumidifiers:
- Ionmax+ ED12
- Ionmax+ ED18
Desiccant vs compressor dehumidifiers — which to choose?
- Desiccant dehumidifiers (like the Ionmax ED12/ED18) are ideal for cold climates, release warm air, and work in freezing temperatures.
- Compressor dehumidifiers (like the Ionmax Rhine) are better for hot and humid conditions — such as summer in Queensland or the NT.
IN DEPTH: Desiccant vs Compressor dehumidifiers
Bonus tips for getting the most out of your dehumidifier
- Position it away from walls and large furniture for optimal airflow
- Close windows and doors while in use
- Monitor your indoor humidity with the Ionmax Q10 Air Quality Monitor
- Clean your filter regularly and set up drainage if running the unit continuously
Learn more about choosing the right dehumidifier in our beginner's guide to choosing the right dehumidifier.
Pick smart, stay dry
Choosing the right-sized dehumidifier for your space is key to enjoying a dry, comfortable, and mould-free home. Whether you're drying laundry indoors, battling condensation, or protecting your storage room from damp — there’s an Ionmax unit designed for the job.
👉 Shop all Ionmax dehumidifiers
👉 Need help choosing? Contact our team
