Silentnight Airmax Mattress Topper reviewed

The Silentnight Airmax Mattress Topper is an 8cm dual-layer hollowfibre topper with air-mesh side walls, rated medium by Silentnight and priced from £41 for a king. Its packaging calls it the Airmax 800, the middle depth of the Airmax range between the 3cm Airmax 300 and the 10cm Airmax 1000.

Construction

The Silentnight product page describes a dual-layer build deeply filled with hollowfibre and mesh sides that let air move freely around your body so you do not overheat.

Why airflow matters

Fibre toppers hold less heat than memory foam, and the mesh sides add a route for warm air to escape. That is relevant because heat disrupts sleep: a review in the Journal of Physiological Anthropology (Okamoto-Mizuno and Mizuno, 2012) found that heat exposure increases wakefulness and reduces deep and REM sleep. An 8cm fibre layer softens a mattress noticeably while staying fairly cool.

Sizes and prices

Prices are Silentnight’s regular prices, checked in September 2026. Only king and super king could be ordered from Silentnight; the same 8cm topper is listed in single and double at Argos. Delivery takes 2 to 3 working days.

Two caveats apply. Hollowfibre compresses over months of use and needs shaking out, and no topper corrects a mattress that has lost its support. Oddly, Silentnight prices the thinner Airmax 300 above this one in king size, so check both before buying.

Which Airmax depth?

Depth decides how much the topper changes your bed. The 3cm Airmax 300 is a refresh layer, the 8cm Airmax adds clear softness, and the 10cm Airmax 1000 is the plushest. At Silentnight the 8cm model is the cheapest of the three in king size, at £41, which makes it the value pick if you have a king or super king bed.

For allergy sufferers there is a catch. The cover is washable at 40°C, below the 60°C that Allergy UK says is needed to kill dust mites, so washing reduces allergen for a while but does not remove the mites themselves.