Six hacks for Japan's humid summers

1. Ventilate with a purpose

Run the bathroom fan for several hours and open windows on opposite sides of the home on dry days to create airflow.

2. Wipe, do not just dry

Wipe bath walls with a towel; it removes the soap film mould feeds on.

3. Move furniture off the wall

A few centimetres of space lets air circulate and stops damp patches behind wardrobes.

4. Drain-cover habit

Remove hair from the drain cover each time you bathe; once a week wash the cover with a brush.

5. Dry shoes and umbrellas

Wet shoes left in the entrance create odours. Dry them near a fan before storing.

6. Use a dehumidifier in closets

Put a moisture absorber in wardrobes and under beds during the rainy season; replace when full.

Why Japanese summers are hard on homes

Japan's rainy season and summer combine high temperature with humidity above 70 percent for weeks. Damp air does not just feel unpleasant: it slows drying, encourages mould and mites and makes smells linger in fabrics. Small flats with limited cross ventilation suffer most. Controlling humidity is the main goal, and cleaning plays a supporting part, because a clean surface has less for mould to feed on.

Use the air conditioner and dehumidifier wisely

The dry mode on an air conditioner removes moisture and is often cheaper than cooling. A portable dehumidifier in the wardrobe room or the bedroom helps when laundry dries indoors. Clean the filters of both machines regularly, because a clogged filter reduces effect and can spread odours. Aim for a humidity of around 50 to 60 percent, and a cheap hygrometer will tell you how close you are.

Protect the places that never get sun

Wardrobes, shoe cupboards, the space behind furniture and the area under the bed hold damp air. Leave a small gap between furniture and the wall, open wardrobe doors on dry days and use moisture absorbers. Do not pack clothes too tightly. Wipe the inside of the shoe cupboard now and then, and let shoes dry fully before storing them. Bedding should be aired or dried on a sunny day to keep mites down.

Bathrooms, laundry and the drain

Follow the bathroom routine: rinse with cold water, wipe, ventilate. For laundry, use a fan or the dehumidifier to dry indoors quickly, and do not leave wet washing in the machine. Clean the washing machine drum and filter monthly in summer, because residue builds up and produces odours. Keep sink and bathroom drains clean, since the heat speeds up smell. If you are away for weeks, leave the bathroom door and a window slightly open to prevent a mouldy return.

Quick answers

What humidity should I aim for? Around 50 to 60 percent. Is it better to use dry mode or cooling? Dry mode is often gentler and cheaper when you mostly want to reduce humidity. How often should I clean the filters? Every two to four weeks in summer. Is vinegar good for mould? It can help on light surface mould in some places, but it is not a substitute for the proper product, and it should never be mixed with chlorine.

A seven-day summer reset

Day one: check the air conditioner filters and wash them. Day two: clean the bathroom thoroughly, including seams and the ventilation cover. Day three: open wardrobes, wipe and add absorbers. Day four: clean the washing machine drum and filter. Day five: wipe the shoe cupboard and air shoes. Day six: air bedding and vacuum the mattress. Day seven: check behind furniture and under the bed. Repeat each month through the humid season.

Travel and long absences in summer

If you leave the home for a week or more in summer, prepare it: empty the fridge and wipe it, take out the rubbish, clean the bathroom and leave the door open, empty the washing machine and leave the door ajar, and place moisture absorbers in wardrobes. Run the air conditioner in dry mode for a short time before leaving, if safe to do so. A short preparation prevents the musty smell and mould you would otherwise find on return.