One small twist of your dial can change everything.
Across the UK, parents, renters and pet owners face the same itchy reality as heating goes on and windows stay shut. Dust mites and bacteria thrive in warmth and moisture. A single laundry setting, used correctly, can cut their numbers fast and help calm sniffles, coughs and poor sleep.
Why mites surge as heating goes on
Dust mites are tiny arachnids that feed on shed skin and pet dander. They love warm, humid textiles. Bedding, pillows and soft furnishings provide ideal conditions, especially after a night’s sweat and breath. Mites leave behind faecal particles that trigger sneezing, wheeze, itchy eyes and eczema flares. Children and people with asthma feel it first.
As rooms get sealed against the cold, indoor humidity can climb. That is when colony numbers rise. A mattress can harbour millions. Yet they are vulnerable to heat and thorough drying, which you control with your machine and your routine.
Set your washing machine to 60°C for sheets, pillowcases and cotton bedding to kill dust mites and reduce bacterial load in one wash.
The single setting that breaks the cycle
Experts in household hygiene point to a 60°C wash for standard cotton bed linen and towels. That level of heat damages mite proteins and curbs common bacteria. Lower temperatures can shift allergen particles into the water, which helps temporarily, but mites may survive and repopulate fabric quickly.
Choose a cotton or hygiene programme that genuinely reaches 60°C. Many eco cycles sit closer to 40°C to save power. Check your manual or display. Pair the hot wash with a full rinse and proper spin to move allergens out of the weave.
Step-by-step: a weekly bedding reset
- Check care labels. Most cotton sheets and pillowcases tolerate 60°C. Delicates may not.
- Load to three-quarters full. Crowded drums trap grime and reduce heat penetration.
- Select 60°C on a standard or hygiene cycle. Avoid quick-wash here; time at temperature matters.
- Use a quality biological detergent for body soils. Enzymes help, heat finishes the job.
- Run an extra rinse if pollen, pet hair or eczema is a problem.
- Dry to bone-dry. Use a tumble dryer on medium–high heat or line-dry in moving air until no damp remains.
- Repeat weekly for pillowcases and sheets. Wash duvet covers every 1–2 weeks. Launder duvets and pillows by season, or choose machine-washable inserts more often if symptoms spike.
Dry until fully dry. Damp bedding invites mould, keeps humidity high and brings mites roaring back.
Why 40°C often fails
A 40°C wash can lift sweat salts and many stains with the right detergent, yet mites handle that warmth. Allergen particles may rinse away, but survivors rebuild numbers within days if conditions stay humid. That is why people feel short-lived relief after a gentle wash and then wake stuffy again by midweek.
Ventilation: the no-cost habit that boosts your wash
Heat kills; airflow prevents regrowth. Each morning, fold back your duvet and blankets. Open a window for 10 minutes to let moist air out. Sunlight helps too. Let the mattress surface breathe before you make the bed. This small ritual reduces humidity in fibres, which makes life harder for mites and bacteria.
Between-wash tactics that actually work
- Use zippered pillow and mattress protectors. Wash them at 60°C every fortnight.
- Vacuum mattresses and headboards with a HEPA-filter machine once a month.
- Keep bedroom humidity near 40–50%. A dehumidifier or trickle vents can help in winter.
- For soft toys, bag and freeze at −18°C for 24 hours, then wash to remove allergens.
- Rotate two sheet sets. Fresh linen on the bed, the other set washed and fully dried.
Costs, time and comfort: what the numbers look like
Heating water uses more energy than drum tumbling. The jump from 40°C to 60°C raises energy use, but the difference per load is modest for most machines. The pay-off is healthier sleep, especially for allergy-prone households.
| Setting or action | Typical time | Effect on mites/bacteria | Approx. energy | Indicative cost |
|---|---|---|---|---|
| 40°C cotton cycle | 60–90 mins | Removes some allergen; mites often survive | ~0.6–0.8 kWh | £0.15–£0.22 (at 25–28p/kWh) |
| 60°C hygiene/cotton cycle | 90–120 mins | Kills mites and curbs bacteria in one wash | ~0.9–1.3 kWh | £0.23–£0.36 |
| Tumble dry to fully dry | 45–70 mins | Heat and airflow remove residual moisture | ~1.5–3.0 kWh | £0.38–£0.84 |
Depending on tariff and machine, the 60°C upgrade can add roughly 10p–25p per wash compared with 40°C. Many households save that back by skipping repeat “failed” washes and by sleeping better.
Fabric care and exceptions
Colour-fast cotton and most pillow protectors handle 60°C well. For silk, wool, viscose or mixed synthetics, follow the label. If 60°C is not allowed, wash at 40°C with a longer cycle, then dry thoroughly and use protective covers. Treat stains before hot washing to avoid setting them. Separate darks to avoid dye run at higher temperatures.
Always read the label: if a fabric cannot take 60°C, protect it with covers you can wash hot.
Signs your new routine is working
Mornings feel clearer. Fewer sneezes on waking. Less night-time itching. Children cough less. You find less fine dust when you shake the duvet. These are good signals that heat, airflow and routine are tipping the balance in your favour.
What specialists look at when they test homes
Humidity and temperature drive mite growth. Keep bedrooms near 18°C and relative humidity around 45%. Space beds from external walls to reduce cold spots that trap condensation. Close the bathroom door during showers and run the fan. Small steps keep microclimates under control.
A practical weekend plan for busy households
Friday night: strip beds and pile linen by the machine. Saturday morning: run a 60°C cycle on sheets and pillowcases while you air the mattresses with windows open. Midday: tumble dry to fully dry or line-dry in moving air until crisp. Afternoon: fit fresh linen and zip protectors. Sunday: wash protectors or spare sets so a clean backup sits ready.
Risks, trade-offs and how to manage them
- Shrinkage: pre-wash new cotton at 40°C, then move to 60°C on later cycles.
- Dye run: wash brights separately the first few hot cycles.
- Energy: stack hot washes in one block so the heater starts from warm water.
- Machine hygiene: run a monthly empty 60–90°C maintenance cycle to clear biofilm.
One habit, once a week: 60°C wash, full dry, 10 minutes of fresh air. That trio starves mites and helps you breathe easier.
Key term to know: relative humidity. It is the amount of moisture in the air compared with the maximum it can hold at that temperature. Mites thrive above roughly 50%. A small digital meter on the bedside table helps you track it. If readings sit high, ventilate, reduce drying indoors, and consider a compact dehumidifier for the room where you sleep.
Parents often ask about cuddly toys. Many bear “surface wash only” labels. When allergies bite, place the toy in a freezer bag for 24 hours to disable mites, then wash gently to remove allergen dust and dry fully. Rotate favourites so bedtime still feels safe and familiar.
