Allergy-Friendly Duvets: Washing at 60C and Barrier Covers

calendar Oct 31, 2026 / · 7 min read · togs bedding duvet  ·
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Why 60C matters for dust mites, and why a 40C duvet label falls short

Two anti-allergy duvets on sale in the UK, from Silentnight and Slumberdown, have a 40C wash on the label. Washing at 60C or above kills house dust mites, while a cooler wash only partly kills them.

House dust mites are about a quarter of a millimetre long. In people allergic to them, the symptoms often come from proteins in the mites' droppings rather than from the mite itself. Each mite produces about 20 droppings a day, and they go on causing allergic symptoms after the mite has died. A significant amount of exposure to the allergen happens in bed.

The allergen dissolves in water, so a lower-temperature wash rinses it out of the duvet for a while. The mites that survive then produce more allergen.

Two routes: a duvet you hot-wash, or a duvet you encase

There are two ways to keep the duvet itself low in allergen: put it inside an allergen-proof barrier cover, or wash it on a 60C cycle. Allergy UK advises covers on every duvet, so the two can be combined.

Barrier covers come as mattress covers, duvet covers and pillowcases. Encasing the bedding is the single most effective measure, and it is not enough on its own.

With an encased duvet, the hot wash moves to what sits outside the cover: sheets and blankets go in every week. A duvet with no cover goes on a 60C cycle itself, so a duvet whose label allows only 40C needs the cover.

What "anti-allergy" on a duvet does and does not mean

On the Silentnight and Slumberdown duvets, the anti-allergy claim rests on the filling and on an Allergy UK approval. Allergy UK lists the approval for the Silentnight range. For the Slumberdown duvet, the approval is the maker's own claim.

Silentnight's anti-allergy bedding is filled with specially treated hollowfibre that helps combat dust mites and bacteria. The range carries the Allergy UK seal of approval. The duvet is machine washable at 40C and comes in 4.5, 7.5, 10.5 and 13.5 tog. Silentnight's hollowfibre pillows wash at 60C, so a matching pillow and duvet from the same brand need different cycles.

Before a size and tog are chosen, the duvet is £16.00, reduced from £18.00; larger sizes and warmer togs cost more.

Slumberdown's Anti Allergy Duvet has a filling the maker calls tested and approved by Allergy UK, and a 40C machine wash. Warmth runs from 4 to 15 tog, and the 4.5 tog single is £20.00. Not every Slumberdown product is suitable for machine washing and tumble drying, and each product's care label has its own washing instructions.

Read the care label before relying on a hot wash. Bedding inside a barrier cover is not part of the weekly 60C wash.

Duvets that take a 60C wash at home

The Spundown 10.5 tog duvet at Allergy Best Buys is washable at 60C to destroy allergens, fits a domestic washing machine, and is rated for 50 washes without losing shape or comfort.

Sizes are Single 135x200cm, Double 200x200cm and King 225x200cm.

A duvet like this suits the second route: it can be washed at 60C instead of being encased, on the same cycle as the sheets. Barrier covers are still advised for all mattresses, duvets and pillows, so a hot-washable duvet can go in a cover as well.

Choosing a barrier cover

A barrier cover has three requirements. It must be breathable, it must completely enclose the duvet, and it must be tested to stop house dust mite allergen escaping. Breathability matters because water and body moisture have to pass through the fabric.

Astex PRISTINE encasements use fabric with a pore size of 5.9 microns and carry the Allergy UK Seal of Approval. The care schedule is a 60C wash every 4–6 weeks. That is less often than the weekly wash for sheets that sit outside the cover.

The Allergy Best Buys classic barrier cover sets close with allergen-proof zips that seal completely and were tested for allergen hold-out by PMI laboratories in New York. They wash at 60C, dry quickly, need no ironing and have a 10-year guarantee. Duvet cover sizes are Single 135x200cm, Double 200x200cm and King 220x235cm. The single and double match the Spundown duvet's sizes exactly. The king figures do not match (225x200cm for the duvet), so measure your duvet before ordering a king cover.

The AllerGuard duvet protector goes under your ordinary duvet cover; the shop shows prices in the visitor's local currency, with the final price set at checkout.

When the duvet or pillow cannot go in at 60C

If a hot wash is not possible, the item can be dry-cleaned. A cooler wash is better than nothing.

Pillows can go in the freezer instead of the machine. Twelve hours in the deep freeze every month kills the house dust mite. The same method works for soft toys that cannot be washed at 60C: put the toy in a plastic bag in the freezer for at least 12 hours once a month, then wash it at the recommended temperature.

Acaricide sprays are not recommended. They are of limited help, may be an irritant, and children and pets need to avoid them.

The rest of the bedroom routine

Use these measures only once a diagnosis of house dust mite allergy has been made.

  • Stay out of the bedroom while the bed is being stripped, and for at least half an hour after it is remade.
  • Without a mattress cover, vacuum the mattress once a week.
  • Remove padded headboards. House dust mites live in them.
  • An allergic child should not sleep in the bottom bunk, where allergen can fall onto them.
  • Use a dehumidifier to keep indoor humidity under 50% and over 30%.

Avoidance measures lower dust mite allergen but do not remove it completely. Doing one or two things may not make any difference, and doing one or two inconsistently is unlikely to help.

VAT relief on barrier covers

Astex encasements are registered as a Class 1 Medical Device and are VAT exempt for people with chronic allergies.

Allergy Best Buys' total enclosure cover ranges, the Cottonfresh organic cotton covers and the breathable microfibre covers, are VAT-free for qualifying individuals.

The AllerGuard duvet protector is VAT zero rated for VAT-exempt customers.

Check each retailer's terms on who qualifies before you order.

Where to buy

References

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