Can one unit cover a whole house?

Yes, for open layouts under 140 m² if placed centrally with interior doors open. For homes 185 m² and above, using two medium units in high-moisture zones is much more efficient than one massive machine, as closed doors and corners block single-unit airflow.

What Size Dehumidifier Do I Need in Australia?

JUN 15, 2026

Last updated: JUN 15, 2026

257 views, 3 mins read

Wondering what size dehumidifier is right for you? Pick a unit that’s too small, and it will run nonstop all day without ever bringing humidity down to a mold-safe, comfortable range.

Go too big, and you’ll waste money on the upfront purchase cost and unnecessary power bills. Don’t worry — this article will tell you exactly what size dehumidifier you really need.

In this article

1. Understanding How Dehumidifiers Are Sized in Australia 2. Finding the Right Size for Your Space 3. FAQs

Understanding How Dehumidifiers Are Sized in Australia

In Australia, dehumidifier size isn't about physical dimensions—it's about how many liters of water the machine can pull from the air in 24 hours (L/day), measured against your room size in Square Meters (㎡).

As CHOICE Australia notes, advertised room sizes often reflect ideal lab settings rather than real local humidity. Homes in tropical/coastal zones should size up 20–30% for sustained high moisture, while southern temperate homes can follow standard sizing for seasonal damp.

Finding the Right Size for Your Space in Australia

To pick the perfect dehumidifier, you need to look at two things: the floor area of your room in square meters and how damp the room actually feels.

Here is a breakdown of common home spaces in Australia to help you find your match:

what size dehumidifier do i need for different space

1. Small Bedrooms and Home Offices (Up to 20 ㎡)

If you are dealing with winter condensation pooling on your bedroom window sills or a slightly musty wardrobe, you don't need a massive machine.

Recommended Size: 10L to 12L per day.
Why it works: These units are compact, quiet enough to run while you sleep, and easily manage the daily moisture created by breathing and ensuite bathrooms.

2. Open-Plan Living Areas and Apartments (20 to 50 ㎡)

For a medium-sized lounge room, a combined kitchen-dining area, or a small two-bedroom apartment, a small bedroom unit won't be able to keep up.

Recommended Size: 16L to 20L per day.
Why it works: This size provides enough fan power to circulate air across a larger footprint, helping your laundry dry faster indoors and protecting your furniture from mold.

3. Large Families Homes and Damp Basements (50 to 80 ㎡)

If you have a large, open-concept home layout or a downstairs rumpus room that gets incredibly sticky during a humid summer, you need a heavy-duty solution.

Recommended Size: 25L to 30L per day (such as the Newentor 25L model).
Why it works: These high-capacity units are designed to pull massive amounts of water from thick carpets and large volumes of air, preventing structural dampness across an entire floor level.

FAQs

1. Should I keep the doors and windows open or closed while running it?

Always keep them completely closed! Think of your dehumidifier like an air conditioner. If you leave your windows open while running it, the machine will frantically try to dehumidify the entire neighborhood instead of focusing its drying power on your indoor living space.

2. Is it better to buy too big or too small?

Slightly larger is better. An undersized unit runs 24/7, wears out faster, and risks mold. A larger unit reaches target humidity quickly and shuts off, often saving more energy than a struggling small one. Just don't go over 30% of your actual need to avoid wasteful frequent cycling.

3. Do I need a different size for winter?

Yes, especially in southern Australia. Compressors lose efficiency below 15°C. If used mainly for winter dampness, either buy a larger compressor model or switch to a desiccant dehumidifier, which works perfectly down to 1°C.

Bottom Lines

At the end of the day, the right dehumidifier size depends on your space, baseline humidity and local climate. For Australian homes in coastal or tropical areas, size up and prioritise real daily dehumidification capacity over advertised room coverage.

We recommend the Newentor 25L Dehumidifier for most households — efficient, reliable, and perfect for keeping your home dry, healthy and comfortable all year round.