What each one does
- Dehumidifier: pulls water out of the air. Lower humidity stops mould growing.
- Air purifier: filters particles, including mould spores. It doesn't change humidity at all.
Which do you need?
| You notice | Start with |
|---|---|
| Mould on walls, ceilings or in wardrobes | Dehumidifier, and fix the moisture |
| Condensation on windows every morning | Dehumidifier and ventilation |
| Musty smell | Find the damp first |
| Allergy symptoms, no visible damp | Air purifier |
| Both | Dehumidifier in the damp room, purifier in the bedroom |
Perth winters
Mild but wet. Condensation builds overnight in closed bedrooms and in wardrobes on cold outside walls. Aim to keep indoor humidity under about 60%. A cheap humidity gauge tells you where you stand. About one in four Australian homes has a damp problem.
Fix the moisture first
- Run bathroom and laundry fans, and check they vent outside, not into the roof.
- Dry clothes outside or in a vented dryer.
- Open up on dry, sunny afternoons.
- Fix leaks and blocked gutters.
- Renting? Report mould and damp to the property manager in writing.
The air inside your home Best purifiers for allergies
Sources
- Knibbs L.D. et al. (2018). Damp housing, gas stoves, and childhood asthma in Australia. Medical Journal of Australia.
- US EPA: Guide to air cleaners in the home.