What Is a Cooling Mattress?

What Is a Cooling Mattress?

A cooling mattress is any mattress designed to actively manage body heat during sleep. The goal is simple: keep the surface between you and the mattress from building up the warmth your body sheds overnight, so you can fall asleep, stay asleep, and cycle through deep sleep without thermoregulation getting in the way. The features that make a mattress "cooling" range from open-cell foam construction at the structural level, to gel and phase-change material infusions, to copper-infused layers, to breathable cover fabrics. This guide explains what a cooling mattress actually is, how the cooling tech works, who benefits most, and how cooling foam compares to traditional memory foam.

A cooling mattress is a mattress built with specific features that dissipate body heat during sleep, rather than trapping it. The cooling effect comes from a combination of factors — open-cell foam construction, gel or phase-change material infusions, copper or graphite layers, and breathable cover fabrics. Our Koala mattress range is built around Kloudcell® open-cell foam, with active cooling tech across the tiers — from the Koala Plus to the premium-cooling Koala Polar+ and the luxury Koala Luxe.

Key Takeaways

  • A cooling mattress is designed to dissipate body heat overnight, rather than trap it

  • Per Sleep Foundation, core body temperature naturally drops during sleep — a mattress that fights this works against sleep quality

  • Traditional memory foam (closed-cell) sleeps hot; cooling foam (open-cell, like our Kloudcell®) addresses the airflow problem at the structural level

  • Cooling tech includes open-cell foam, gel infusion, phase-change materials (PCMs), copper or graphite infusion, and breathable covers

  • Hot sleepers, those in humid climates, and people experiencing menopausal night sweats often benefit most — for persistent night sweats, see your GP

  • Our cooling foam range covers every tier: Plus, Polar+, and Luxe

What is a cooling mattress?

A cooling mattress is any mattress engineered with construction features that actively manage body heat — rather than letting it build up between you and the surface you sleep on. There's no single industry definition that defines what's "cooling enough" to wear the label, but the practical meaning is consistent: a cooling mattress is one that's been designed at the structural and cover level to either dissipate, absorb, or conduct heat away from your body during the night.

This separates cooling mattresses from traditional foam mattresses (which often trap body heat) and from generic innerspring mattresses (which may have natural airflow through the coils, but typically lack the cover and comfort-layer features that make a meaningful difference for hot sleepers).

In Australia, where summer nights regularly stay above 20°C even after dark, cooling mattresses have moved from "nice-to-have premium feature" to a meaningful sleep-quality decision for many sleepers.

How does a cooling mattress work?

Cooling mattresses work by changing the thermal exchange between your body and the sleep surface. Three mechanisms do the work:

Heat dissipation. Open-cell foam structures, channel ventilation, and breathable covers allow body heat to move away from the surface rather than building up underneath you.

Heat absorption. Materials like gel beads and phase-change materials (PCMs) actively absorb body heat as you sleep, then release it gradually when the surface cools.

Heat conduction. High-conductivity materials like copper or graphite physically draw heat away from the contact surface and disperse it laterally through the mattress.

The reason this matters is well established. Per Sleep Foundation, core body temperature naturally drops at the onset of sleep and stays lower during deep sleep and REM stages. A mattress that traps body heat works against this thermoregulation — your body fights to cool itself, which fragments sleep architecture and shortens the deeper, more restorative phases of sleep.

A well-designed cooling mattress doesn't make you cold. It removes the obstacle your body has to work around to reach and sustain healthy sleep stages. For more on how mattress features affect sleep quality broadly, see our what makes a deep dream mattress guide.

Cooling foam vs traditional memory foam: what's the difference?

Traditional memory foam — the classic Tempur-style viscoelastic foam — is built on a closed-cell structure. Closed-cell means the foam bubbles are sealed; air can't pass through them. This is excellent for pressure relief (the foam compresses precisely around your body), but it traps heat. The warmth your body releases has nowhere to escape, so it builds up under you through the night.

Cooling foam takes a different structural approach. Open-cell foams (including our Kloudcell®) have interconnected bubbles that allow airflow through the foam itself. Body heat can dissipate through the foam structure rather than being trapped against your skin. This is the baseline cooling advantage — and it's structural, not a marketing claim added on top.

Beyond the cell structure, modern cooling foams add active cooling tech (gel infusion, copper, phase-change materials) on top of the open-cell baseline. The compound effect is what makes the difference: a mattress with open-cell foam plus gel infusion plus a breathable cover sleeps meaningfully cooler than a mattress with just one of those features.

Cooling foam isn't strictly "better" than memory foam in every dimension — closed-cell memory foam can offer a deeper pressure-relief contour. But for hot sleepers, those in humid climates, or anyone who's woken up sweaty on a memory foam mattress, the open-cell structure is the right call.

If you're weighing a cooling foam mattress for purchase, our best cooling foam mattress guide covers the AU-specific shopping decision in detail — including a side-by-side cooling-tech comparison table and the Koala range mapped to hot-sleeper use cases.

Cooling tech inside the mattress

Five cooling technologies you'll find inside modern cooling mattresses, and what each one actually does:

Open-cell foam. The structural foundation. Interconnected foam bubbles let air move through the foam itself, preventing heat build-up at the structural level. All our Koala mattresses are built on Kloudcell® open-cell foam.

Gel infusion. Small gel beads or layers are added to the foam comfort layer. The gel absorbs body heat as it builds up and disperses it laterally, so heat doesn't concentrate under your body. Found in our Koala Plus (Cooling Gel Kloudcell®).

Phase-change materials (PCMs). A more advanced cooling mechanism. PCMs are materials that shift between solid and liquid states as they absorb heat — they actively pull thermal energy away from your body and store it temporarily. Found in our Koala Luxe.

Copper or graphite infusion. Copper has high thermal conductivity — it physically conducts heat away from contact points faster than untreated foam. Graphite does similar work. Our Koala Luxe uses copper-infused Kloudcell® for this reason.

PolarBands™. A Koala-exclusive heat-management technology built into our Koala Polar+. Highly thermally conductive bands are embedded in the summer-side layer around the centre of the pillow or mattress, where heat usually concentrates, to conduct it away from the body. The Polar+ sleeps up to 5°C cooler than our standard Plus, per our product page.

Cover materials and surface cooling

A cooling foam core can lose much of its advantage if the cover material traps heat at the surface. Cover material matters because most of the immediate thermal exchange happens at the top layer — between you and the cover itself.

TENCEL™ Lyocell is widely regarded as one of the best cooling cover materials. Per Lenzing, TENCEL™ Lyocell absorbs moisture more effectively than cotton and breathes well in humid conditions — meaningful for AU summers.

Cotton is naturally breathable and a strong baseline cooling material, though it doesn't manage moisture as actively as TENCEL™ Lyocell.

Bamboo viscose is breathable and moisture-wicking; popular in cooling mattress and bedding products.

CoolThread™ is a cool-to-the-touch fabric used in some specialised products (including our Koala Pillow [2nd Gen]).

Polyester-heavy covers typically aren't well-suited to hot sleepers — synthetic fibres tend to trap heat and moisture against the skin. Many lower-tier "cooling" mattresses cut corners at the cover layer, which often undoes much of the cooling work the foam core was meant to do.

Who benefits most from a cooling mattress?

Cooling mattresses aren't only for people who run hot at night. The sleepers who tend to benefit most:

  • Hot sleepers — people who naturally run warm at night, often shedding bedding or waking sweaty

  • Sleepers in humid climates — particularly humid coastal Australia (Sydney, Brisbane, Gold Coast, Cairns), where summer nights stay sticky long after sunset

  • People experiencing menopausal or perimenopausal night sweats — cooling mattresses can ease the surface-temperature factor, though for persistent or severe night sweats, see your GP. AU resources like Jean Hailes for Women's Health can help with broader guidance

  • Heavier or more athletic sleepers — more body mass means more heat generation; cooling tech helps the mattress keep up

  • Partners with different temperature preferences — a cooling mattress can keep the warmer-sleeping partner comfortable without freezing the cooler-sleeping partner

If you're looking specifically at how to choose a cooling foam mattress for AU summers — including which Koala model fits which climate and sleeper profile — our best cooling foam mattress guide breaks down the decision in detail.

Common myths about cooling mattresses

Four cooling mattress myths worth busting:

Myth 1: All foam mattresses sleep hot. False — this is only true of closed-cell traditional memory foam. Open-cell foams (like our Kloudcell®) actually breathe well structurally; the cooling tech added on top makes them strong cooling performers.

Myth 2: Cooling sheets fix a hot mattress. Partially true — better sheets help, but they're only one layer. If the mattress core traps heat, you'll still sleep hot regardless of what's on top. The cover and core matter together.

Myth 3: Air-conditioning replaces a cooling mattress. False — air-con cools the room, but localised body-mattress heat is the bigger driver of sleep disruption. Per Sleep Foundation research, the contact heat between body and surface is what fragments sleep architecture, not the ambient room temperature alone.

Myth 4: Cooling mattresses are only useful in summer. False — temperature regulation matters year-round. Even in winter, body heat builds up overnight under bedding; a cooling mattress prevents the surface from becoming uncomfortably warm regardless of the season. For winter-specific bedding context, see our best winter bedding guide.

Choosing the right cooling mattress for you

If you've worked out a cooling mattress is the right fit and you're ready to compare specific options:

Time to upgrade to a cooling mattress?

If your current mattress is making warm nights uncomfortable, our cooling foam range is built specifically for that problem. Shop the Koala Polar+ (premium cooling), Koala Plus (mid-tier cooling), or browse the full Koala mattress range — all backed by our 120-day trial with free pickup if it's not the right fit.

Shop our cooling mattress range →

 

 

Frequently Asked Questions

What makes a mattress "cooling"?

A mattress is "cooling" when it's been built with construction features that dissipate body heat rather than trap it. The specific features can include open-cell foam (rather than traditional closed-cell memory foam), gel infusion, phase-change materials, copper or graphite layers, and breathable cover materials like TENCEL™ Lyocell or cotton. There's no single industry definition of "cooling enough," but the consistent meaning is a mattress designed to actively manage body heat overnight.

Is cooling foam better than memory foam?

For hot sleepers and humid climates, yes — open-cell cooling foams (like our Kloudcell®) breathe better than traditional closed-cell memory foam because the foam structure itself allows airflow. For sleepers who specifically want a deep pressure-relief contour and don't run hot at night, traditional memory foam still has its place. The best-of-both-worlds approach — which our Koala mattresses take — is open-cell foam with active cooling tech layered on top.

Do cooling mattresses really work?

Yes — though "work" means different things at different price points. Entry-level "cooling" mattresses that rely only on a gel-infused cover and traditional closed-cell foam underneath often disappoint. Mattresses with structural open-cell foam plus active cooling tech (gel, PCMs, copper, or PolarBands™) plus a breathable cover (like TENCEL™ Lyocell) compound their cooling effect and produce meaningful temperature differences. Our Koala Polar+ sleeps up to 5°C cooler than our standard Plus per our product page — a verified, measurable difference.

Are cooling mattresses worth the extra cost?

For hot sleepers, sleepers in humid AU climates, or anyone who's been waking sweaty on a regular mattress — yes, the cooling-tech premium pays back in sleep quality. For sleepers who don't run hot and live in temperate climates, the extra spend may not be necessary. The mid-tier ($1,200–$2,000 queen) is usually the sweet spot for getting strong cooling tech without paying for luxury features you don't need. For the broader price decision, see our mattress cost guide.

Which Koala mattress is the coolest?

Among our range, the Koala Polar+ is our coolest-sleeping mattress — PolarBands™ over Cooling Kloudcell® means it sleeps up to 5°C cooler than our standard Plus per our product page. The Koala Luxe is also a strong cooling pick with copper-infused Kloudcell® and phase-change materials, particularly for sleepers who want 7-zone luxury support combined with cooling tech. The Koala Plus is our mid-tier cooling option for moderate hot sleepers. For more on how to choose between them, see our best cooling foam mattress guide.

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