Best Dehumidifier Australia 2026: Buyers' Guide

Quick answer: for most Australian homes, mould problems and single-room water damage, a 50L/day LGR dehumidifier is the best all-round choice; step up to 70L for multi-room drying and larger commercial spaces, and 90L for warehouses, severe flooding and 24/7 restoration work. Whatever the size, buy an SAA-certified unit with a continuous drain, auto defrost and a compressor rated to keep extracting below 10°C.

Choosing the best dehumidifier Australia has to offer is harder than it should be. Our climate ranges from tropical Darwin humidity to cold, damp Melbourne winters, and the "litres per day" number on the box is measured in lab conditions most rooms never see. This guide explains what actually matters — capacity, LGR technology, certification and drainage — then compares the three Thorair models (50L, 70L and 90L) so you can match a unit to your room, your mould problem or your water damage job. Every spec and price below is taken from the live product pages on thorair.com.au as at September 2026.

What makes a dehumidifier "best" in Australia?

A dehumidifier that works well in a European apartment can struggle in an Australian garage in July. The four things that separate a good unit from a disappointing one are:

• Extraction rate (L/day) at realistic conditions. Ratings are quoted at 26–30°C and 80–90% relative humidity (RH). In a 20°C room at 60% RH the same machine removes far less. Compare units at the same rating conditions and size up if your space is cool.
• Low-temperature performance. Standard refrigerant units ice up and slow down below about 15°C. LGR (Low Grain Refrigerant) units pre-cool incoming air so they keep pulling water out of cool, damp air — the Thorair 50L is rated to operate down to 2°C.
• SAA/ASA certification. Electrical equipment sold in Australia must meet local safety standards. An SAA-certified plug and unit protects you, your insurance claim and your warranty.
• Continuous drainage and auto defrost. If you want to run the unit unattended for days, you need a drain hose connection and a defrost cycle. Tank-only domestic units fill up overnight and shut off.

Why Australians invest in a quality dehumidifier

Mould and health

Mould needs sustained humidity above roughly 60–65% RH to grow. Holding indoor air between 40% and 55% RH removes that fuel, which is why a properly sized dehumidifier for mould is the first thing restorers install after a leak. Lower humidity also means fewer dust mites and less of that musty smell in wardrobes and bathrooms.

Water damage and floods

After a burst pipe, storm or flood, the clock is running: mould can establish within 48–72 hours on wet plasterboard and carpet underlay. Commercial dehumidifiers paired with air movers pull moisture out of materials faster than ventilation alone, which is what limits the demolition and rebuild bill.

Protecting the building and contents

Persistent damp swells timber, delaminates flooring, corrodes electronics and ruins stored stock, which is why warehouses, archives and self-storage facilities run dehumidifiers year-round.

Refrigerant vs LGR vs desiccant: which type do you need?

There are three technologies on the Australian market. Most buyers only need to understand the first two.

• Standard refrigerant (compressor) units are the most common and the most efficient in warm, humid rooms above about 15°C. Fine for a lounge room in Brisbane; weak in a Canberra basement.
• LGR (Low Grain Refrigerant) units are refrigerant dehumidifiers with an extra heat-exchange stage that lets them keep extracting at lower temperatures and lower humidity. This is the professional standard for water damage restoration, and it is what all three Thorair models use.
• Desiccant units use a moisture-absorbing wheel instead of a compressor. They work at very low temperatures (cold rooms, unheated sheds in alpine areas) but use more power per litre removed and warm the air noticeably. Specialist use only.

For homes, offices, restoration and most commercial sites in Australia, LGR is the safe choice: it covers the warm coastal summers and the cool southern winters with the same machine.

Thorair 50L vs 70L vs 90L: side-by-side comparison

All three units are LGR machines with wheels, digital controls, auto defrost, a continuous drain connection and SAA certification. The differences are capacity, airflow and footprint.

All three ship free Australia-wide, except Western Australia ($50) and Tasmania ($200). Browse the full range in the dehumidifier collection.

How to size a dehumidifier: by room and by water damage

Sizing is where most people go wrong. Too small and the job drags on for weeks while mould gets a head start; too large is rarely a problem in restoration, but it is wasted money for a bedroom. Use the two methods below as a starting point, then confirm with a moisture meter or a call to our team.

Sizing by room (general damp and mould control)

These indicative figures assume a standard 2.4–2.7 m ceiling and a closed space. Cool rooms, leaky old houses and coastal locations sit at the top of each range.

• Up to about 60 m² (a large bedroom, bathroom and hallway, a granny flat, a small office): 50L.
• Roughly 60–120 m² (a whole single-storey home with doors open, an open-plan office, a café or gym): 70L.
• Over 120 m² (warehouses, halls, indoor pools, multi-level buildings): 90L, or several units placed across the space.

Sizing by water damage class (restoration drying)

Restorers size on how wet the materials are, not just floor area, because a dehumidifier has to keep up with the moisture that air movers are pulling out of carpet, underlay, plasterboard and timber.

• Class 1 – small area, little absorption (a washing machine overflow on tiles or a small carpeted room): one 50L unit with two or three air movers.
• Class 2 – whole room, carpet and underlay saturated, water wicked up walls: one 70L unit for a typical room, or a 50L in each room with the doors closed, plus an air mover every 3–4 linear metres of wet wall.
• Class 3 – ceilings, walls, insulation and floors all wet (storm damage, burst pipe upstairs): a 90L unit per large area, air movers on every wet surface, and a HEPA air scrubber if there is any contamination — see our water damage restoration equipment.
• Class 4 – dense materials such as hardwood, concrete and brick: LGR units are essential, drying takes longer, and you will usually run multiple machines and monitor daily.

Rule of thumb: if you are drying more than one room at a time, or the water has been sitting for more than 24 hours, go up one size. Pair the dehumidifier with our carpet dryers and air movers — a dehumidifier removes moisture from the air, but it is the air movers that get the moisture out of the materials in the first place.

Features to check before you buy

• Digital humidistat. Set a target RH (45–50% for homes, lower for structural drying) and let the unit cycle itself instead of running flat out.
• Washable filter. Restoration air is full of dust and fibres. A washable pre-filter (fitted to the 70L and 90L) keeps airflow up and saves buying replacements.
• Wheels and a solid handle. A 40–50 kg machine gets moved a lot. The 70L uses semi-pneumatic tyres for stairs and gravel driveways.
• Drain hose length. The included hose reaches a nearby sink or floor waste; for anything further, a 7.5 m dehumidifier hose is a cheap add-on.
• Warranty and local support. The Thorair 50L carries a two-year warranty, and every model is supported from Australia with parts and phone advice on 1300 263 551.

Maintenance tips

• Rinse or replace the filter every one to two weeks in restoration use, and monthly in a home.
• Keep 30–50 cm of clear space around the intake and outlet, and run the drain hose downhill with no kinks.
• Close doors and windows. A dehumidifier fighting outside air on a humid day will run forever and achieve little.
• For commercial fleets, log run hours and book a service check annually to protect the warranty.

Best dehumidifier Australia: frequently asked questions

What is the best dehumidifier for mould in Australia?

For a bedroom, bathroom or small unit, a 50L LGR dehumidifier with a humidistat set to 45–50% RH will stop mould growth and dry out the existing damp. For a whole house or a persistent problem in a cool, damp home, choose the 70L. Always fix the water source first — a dehumidifier manages humidity, it doesn't stop a leak.

How do I choose between 50L, 70L and 90L?

Match capacity to the area and how wet it is: 50L for single rooms and light damp, 70L for whole homes, offices and most restoration jobs, 90L for warehouses, severe flooding and 24/7 drying. When you're on the fence, go larger — a bigger unit finishes sooner and cycles off, so it doesn't necessarily use more power over the job.

Do I really need an LGR dehumidifier?

If the space will ever be below about 15°C — basements, garages, southern-state winters, any restoration job — yes. LGR units keep extracting where standard refrigerant units ice up. In a consistently warm coastal room a standard unit will work, but LGR gives you one machine that covers every job.

How much water will it actually remove per day?

Less than the rating in normal conditions. The 50L rating is measured at 30°C and 80% RH; a 20°C room at 60% RH might yield a third to half of that. That's normal for every brand, and it's why sizing up matters in cool rooms.

Are Thorair dehumidifiers SAA certified?

Yes. The 50L is SAA certified, and the 70L and 90L are SAA and ASA certified for supply and use in Australia. Certification details are listed on each product page.

Where can I buy a commercial dehumidifier in Australia?

Thorair supplies 50L, 70L and 90L LGR dehumidifiers from stock, with free delivery on dehumidifiers Australia-wide (WA $50, TAS $200). Restorers starting out can also buy dehumidifiers bundled with air movers and air scrubbers in our start-up packages.

Find the best dehumidifier for your project

Compare the Thorair 50L, 70L and 90L LGR dehumidifiers online, or call 1300 263 551 for sizing advice on a specific room, mould problem or water damage job. Every unit is SAA certified, in stock in Australia and ships free to most states.