New Wool Bedding Research Confirms Superior Sleep Performance

New research commissioned by British Wool in partnership with IWTO demonstrates wool’s measurable advantages in sleep products. The BioComposites Centre at Bangor University tested wool duvets against synthetic polyester, feather & down, and 100% down alternatives, examining the two factors most critical to sleep comfort: thermal insulation and moisture management.

This work adds to the body of existing research into wool’s benefits for sleep. We break down the results for you here.

Better Insulation, Even With Less Loft

Wool duvets consistently outperformed other fillings in thermal testing, showing 25% better insulation than synthetic options, 30% better than feather & down, and 17% better than pure down.

This superior performance challenges a common consumer misconception. Wool duvets often appear thinner and less voluminous than alternatives, leading shoppers to assume they provide less warmth. This research proves the opposite.

During eight-hour temperature monitoring, wool maintained a centre temperature of 22°C compared to just 13-15°C in other types of duvets. The wool duvet lost only 20% of heat from bottom to middle versus 34-47% in alternatives.

Dynamic Moisture Management

Tests on the levels of moisture transmission reveal wool’s most impressive advantage. Moisture transmission refers to how effectively moisture (water vapour from persperation) moves from the body through the bedding material and into the surrounding air.

At normal body temperature, wool transmitted substantially more moisture than competing materials. Then, as conditions became more demanding, wool’s performance scaled dramatically.

At elevated temperatures simulating increased perspiration, wool transmitted up to 139% more moisture than synthetic duvets, 151% more than feather & down, and 50% more than down alternatives.

Why moisture management matters for sleep

Effective sleep comfort depends on how quickly perspiration can be transported away from the body and released to surrounding air. Good moisture transmission means

• Perspiration travels away from the body quickly
• You stay drier and more comfortable
• Your body’s natural thermoregulation works efficiently

In contrast, slow moisture movement creates elevated humidity within bedding, resulting in that clammy, overheated feeling that disrupts sleep.

Wool Works Faster

Beyond moving more moisture, wool also works faster.

The transmission rate testing showed wool moving moisture up to 120% faster than synthetic options, 153% faster than feather & down, and 49% faster than down.

As humidity levels increased, wool nearly doubled its transmission speed, while other materials showed only modest improvements from much lower baselines.

Taken together, this means that wool is an incredibly efficient mover of moisture, supporting our natural thermoregulation so that we can a great night’s sleep.

The complete research methodology and detailed findings are available in the full report, including technical specifications and comparative data across all testing protocols.

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