Cooling mattress topper

Our cooling mattress topper for hot summer nights

On hot summer nights, heat gets trapped between you and the mattress — it draws that heat away with breathable fibres and moisture-regulating structures. A cooling mattress topper goes further: it actively draws heat away from the body and channels moisture outward instead of letting it evaporate passively. Hefel has developed the Cool mattress topper, combining two technologies: TENCEL (Lyocell) for moisture regulation and PCM (Phase Change Material) for active temperature control. Available in all standard mattress topper sizes. The result: fresh, even sleep temperature through the night, without synthetic sweat-barrier feel

TENCEL and PCM — How the Cooling Works

TENCEL (Lyocell) is a fibre made from wood cellulose that absorbs moisture 50% faster than cotton and immediately releases it to the surrounding air. On the skin, TENCEL feels smooth and cool — a physical effect, not a marketing promise. The surface stays dry even when the body perspires heavily. This is the passive cooling.
PCM (Phase Change Material) is the active component. Micro-encapsulated materials within the fibres melt at a defined temperature — typically around 28 °C — absorbing excess body heat in the process. When body temperature drops, the microcapsules solidify again and release the stored warmth. The effect: the temperature at the body surface remains within a narrow, comfortable range — regardless of whether the night is 18 °C or 30 °C.
The combination of both technologies makes Hefel’s Cool topper the most effective cooling mattress topper in the range. TENCEL keeps the surface dry, PCM keeps the temperature stable. No other material in the Hefel programme achieves this dual effect — pure TENCEL cools passively but cannot store and return heat; wool insulates but cannot actively cool.

For Whom a Cooling Mattress Topper Makes the Difference

People who perspire at night: The most common cause of disturbed sleep. A cooling mattress topper draws heat away where it originates — on the underside of the body, between mattress and sheet. Where duvet and bed linen cannot reach.
Couples with different warmth preferences: On a continuous mattress, PCM balances the temperature across the entire surface — the warmer side is cooled, the cooler side benefits from the returned warmth. This is why Cool is the top recommendation for shared beds.
Residents of top-floor flats: Where the bedroom becomes a sauna in summer, a cooling topper is the first measure — more effective than a fan, quieter than air conditioning.
Combined with linen: A cooling mattress topper under a linen fitted sheet and linen bed linen creates the coolest sleep system at Linen Lounge. Linen regulates moisture from above, the Cool topper regulates temperature from below. Add a Hefel summer duvet made from TENCEL — three layers, one goal: dry coolness.

Genuine Craftsmanship

Crafted by people who have learned their trade over generations.

Sustainability

Material, production, people – genuine sustainability. Fabrics traceable to the Atlantic coast.

Durable

Linen bedding can be washed at low temperatures and becomes softer with each wash.

Breathable

Linen bedding keeps you pleasantly cool in summer and cozy warm in winter. Bedding for all seasons.

Care and the Warm Counterpart

The Cool mattress topper is washable at 60 °C (check label). A gentle spin cycle is recommended to protect the PCM microcapsules. Air dry — the tumble dryer can impair the cooling properties. Air regularly. No fabric softener. Full tips at Care & Durability.
The Cool topper is one of six material variants from Hefel. For warming toppers, the wool mattress topper is the direct counterpart — where Cool draws heat away, wool stores it. Together they cover the entire spectrum. For couples on split mattresses: a Cool topper on the warm side, a wool topper on the cold side. Individual climate, one bed.
For further variants (cotton, Swiss stone pine, Outlast) and all sizes from 90x200 to 200x200, visit the mattress toppers main page. All Hefel products on the Hefel brand page.