Waterproof Dust Mite Mattress Protector & Encasement | 18–24cm

A waterproof mattress protector and encasement for mattresses 18–24cm deep — stretch-knit polyester jersey with a microporous TPU waterproof lining. The three-sided zipper closure with Velcro lock flap fully encloses the mattress, and the membrane's pore structure (approximately 0.16 microns at maximum distribution) means the fabric can be used as a barrier to dust mite particles in the 10–40 micron range as well as to liquids. Available Single, Long Single, King Single, Double, Queen, King, and Super King.

At a glance

• Fabric: 90gsm polyester knitted jersey outer with 0.2mm microporous TPU waterproof lining
• Pore size: Approximately 0.16 microns at maximum distribution (third-party capillary flow porometry, Galwick fluid)
• Surface: Soft, cool, and silent — no plastic crinkle
• Closure: Three-sided U-shape zipper with Velcro lock flap to prevent accidental opening
• Coverage: Encloses all six sides of the mattress
• Mattress depth: Fits mattresses 18–24cm deep; the knit stretches to accommodate up to ~27cm
• Waterproof: Yes — the TPU membrane blocks liquids while remaining breathable
• Care: Machine washable on warm/gentle cycle
• Quality: Manufacturer-backed against defects

What this product is

A full mattress protector and encasement that can be used in homes where dust mite allergens are a concern. The TPU lining provides waterproof coverage for spills; the membrane's pore structure and full enclosure mean the fabric can also be used as a barrier to dust mite particles.

• How the fabric works as a particle barrier. Dust mite allergens are carried by fecal pellets and body fragments that typically measure 10 to 40 microns. The TPU membrane's pores — approximately 0.16 microns at maximum distribution — restrict these particles from passing through the fabric, and the full zippered closure encloses all six sides of the mattress.
• Spill, incontinence, and bedwetting coverage. The TPU membrane is fully waterproof — useful for spills, sweat, incontinence, bedwetting, aged-care needs, or households with pets. The membrane is microporous so the encasement still breathes via water-vapour passage.
• Used alongside other dust mite reduction measures. Encasement bedding is one piece of dust mite reduction in the bedroom, alongside regular vacuuming, hard-floor surfaces where possible, and reduced soft furnishings. If you have a diagnosed condition, discuss bedding choices with your GP or allergist.

Who this is for

• People who want a waterproof layer over the mattress and a fabric that can be used as a dust mite particle barrier
• Households needing both incontinence/bedwetting protection and a dust mite particle barrier
• Carers and aged-care households needing a single layer that handles both spill protection and a dust mite barrier
• People who want a stretch-fit encasement — the knitted jersey accommodates mattresses with non-standard depths or shapes

It's probably not the right fit if:

• You prefer 100% natural fibres — see our cotton mattress encasement instead (cotton is more breathable, but not waterproof)
• Your mattress is over 27cm deep — the knitted jersey stretches to about 27cm, but for deeper mattresses choose our 24–33cm version
• You need a cot-size mattress protector — see our cot mattress protector instead

What the fabric does

Dust mite allergens are carried by fecal pellets and body fragments that typically measure 10 to 40 microns. This fabric's TPU membrane has pores measured at approximately 0.16 microns at maximum distribution (third-party capillary flow porometry, Galwick fluid), well below that, which is why the fabric can be used as a particle barrier in this size range.

• Microporous TPU membrane. The membrane has pores small enough to block liquid water and fine particles, but large enough to let water vapour through. Particles inside your mattress stay inside.
• Fully waterproof. The TPU membrane blocks liquid spills, sweat, and incontinence — useful for bedwetting, aged-care needs, or households with pets.
• Velcro-locked zipper. A three-sided U-shape zipper covered by a Velcro flap, which stops the zip working open over time and seals the closure end.
• Stretch fit. The knitted jersey outer has noticeable elasticity, so it accommodates mattresses with slightly varied depths and is easier to fit than a rigid woven fabric.
• Soft and silent. The jersey outer feels like fabric, not plastic. No crinkle, no rustle.

Sizing

This encasement fits mattresses 18–24cm deep, but the knitted jersey stretches to accommodate slightly thicker mattresses too.

Will it fit my mattress? Measure your mattress depth from the top down to where it rests on the base.

• Under 15cm: this 18–24cm encasement fits, with some slack
• 15–22cm: this 18–24cm encasement is the right choice
• 22–27cm: the knit stretches to accommodate — still fits
• 27cm and over: choose our 24–33cm version instead

How to fit it

For a mattress on a slatted or solid base:

1. Strip the mattress completely.
2. Stand the mattress on its side, leaning against a wall if needed.
3. Unzip the encasement fully and slide it over the mattress from the top.
4. Lay the mattress flat on the bed, then close the zipper around the three sides.
5. Fold the Velcro flap over the zipper end to seal the closure.
6. Place a standard mattress protector on top to absorb daily wear.

For a mattress on an ensemble base or box spring: remove the base legs or wheels first. Slide the encasement over the base, close the zipper, then make small incisions where each leg/wheel attaches and screw them back in firmly through the encasement fabric — this seals the encasement to the base around each leg.

Care

• Before first use: wash the encasement before fitting. This is recommended by the manufacturer to remove any production residues.
• Wash: machine wash on a warm or gentle cycle. Avoid hot water — high temperatures can damage the TPU membrane over time.
• Dry: tumble dry on low/medium heat or air dry. Avoid hot dryers, which can break down the TPU lining.
• Frequency: every 6 months is generally sufficient when a standard mattress protector sits on top to absorb daily wear. The decorative protector above gets washed weekly with your bed linen.
• Avoid: bleach, fabric softeners, dry cleaning, ironing, and any oils or strong detergents.
• Lifespan: over 4–5 years, prolonged exposure to body oils can cause the TPU membrane to break down. Using a mattress protector layer on top significantly extends the lifespan.

Materials and testing

• Fabric: 90gsm polyester knitted jersey outer with 0.2mm TPU (thermoplastic polyurethane) waterproof lining.
• Pore size: approximately 0.16 microns at maximum distribution (third-party capillary flow porometry, Galwick fluid).

We don't make claims that the product cures, treats, or prevents allergies, asthma, or any medical condition. What we describe is the fabric's measurable physical properties as a barrier against fine particles and liquids.

Pairs well with

For a complete bedding setup, customers commonly pair this with:

• Dust mite pillow protectors — one per pillow
• Cotton dust mite quilt encasement — covers the doona
• Mattress Mate slip-on protector — a washable top layer that goes over this encasement and significantly extends its lifespan

Frequently asked questions

What's the difference between this and the cotton mattress encasement?

Both can be used as a barrier against dust mite particles. The differences: the cotton version is 100% natural cotton, OEKO-TEX certified, more breathable, but not waterproof. This version is a polyester knitted jersey with a TPU waterproof lining — it blocks liquid spills as well as particles and has a stretchy fit.

What pore size is needed to limit dust mite allergens?

Dust mite allergens are carried by fecal pellets and body fragments that typically measure 10 to 40 microns. Anything below about 10 microns can be used as a barrier to these particles. This product's TPU membrane has pores measured at approximately 0.16 microns at maximum distribution (third-party capillary flow porometry) — well below that range.

Does it really feel waterproof without feeling like plastic?

Yes. The TPU membrane is laminated behind a soft polyester knitted jersey, so the surface that touches you is fabric. There's no plastic crinkle and no rustle.

Will it make me hot at night?

Less than a fully laminated PVC protector, but slightly more than a 100% cotton encasement. The TPU membrane is microporous — it allows water vapour through, so it breathes — but it's not as breathable as natural fibre.

Does it block bed bugs?

The membrane's pore structure is well below the size of bed bugs or their eggs, and the Velcro-locked zipper closure has no gaps.

Is this suitable for someone with eczema or asthma?

We can describe what the fabric does — it's a TPU-lined polyester jersey with approximately 0.16-micron pores at maximum distribution — but we don't make claims about how that affects any medical condition. If you have eczema, asthma, or another diagnosed condition, please speak with your GP or allergist.

Is it suitable for incontinence or bedwetting?

Yes — the TPU lining is fully waterproof. For heavy or repeated wetting, we recommend layering with a washable top protector to extend the encasement's lifespan.

Can I use it with an electric blanket?

Yes. We recommend placing the electric blanket between the encasement and your normal mattress protector, so the blanket is shielded from spills and the encasement isn't directly heated.

How often should I wash it?

Every 6 months is generally sufficient when a standard mattress protector sits on top to absorb daily wear. If there's been a spill or accident, wash sooner.

What temperature should I wash it at?

Warm or gentle cycle, not hot. High temperatures can damage the TPU membrane over time.

Can I tumble dry it?

Yes, on low or medium heat. Avoid high heat.

Is it noisy?

No. Plastic-backed protectors crinkle when you move; this has a fabric outer and is silent.