Counting Sheep? Research Shows Wool Bedding Boosts Better Sleep

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Counting Sheep? Research Shows Wool Bedding Boosts Better Sleep 

Pioneering research conducted by the University of Leeds (UK) reveals that wool bedding boosts the chances of a good night’s sleep by 67%.

The study, commissioned by The Wool Room and conducted by the University of Leeds Performance textiles and clothing research group, led by senior lecturer Ningtao Mao, pitted commercially available feather/down duvets against polyester and wool to examine their thermal insulation properties and moisture management, factors essential to keeping us cool and preventing a disturbed night’s sleep.

Wadding samples of each duvet were pre-conditioned under two environments: in the cooling down phase from a temperature of 70oC and in the warming up phase of an environment of 17oC and 45% relative humidity – considered to be the ideal settings for the average bedroom. In both environments, it was found that the wool duvet performed significantly better at managing moisture over an 8 hour period than both polyester and feather/down duvets.

Over a third of Brits attribute poor sleep to being too hot at night and it is this build-up of heat and subsequent sweating that is the most common reason for waking during the night, particularly during crucial stage 4 regenerative sleep between 2am – 5am.

Wool's "breathability" + insulating properties key

Moisture management was tested by measuring the water vapour resistance of each sample of wadding, a higher score indicates a fibre that traps moisture, leaving it unable to escape and causing a build-up of heat with subsequent waking. Feather/down wadding allowed the least amount of water to escape, with wool allowing 43% more moisture transmission than polyester and a massive 67% more than feather down duvets. 

When testing thermal insulation, wool was found to reach 35.1oC, the optimum temperature for sleep, faster than feather/down and polyester bedding. It was also found to maintain this temperature constantly while feather/down and polyester took far longer to reach 35.1oC and were unable to maintain this, regularly reaching 36.1oC and above. 

Sweating Guarded Hot Plate technology allowed the wadding to be tested in conditions that mimic the human body during the night. When applied to a typical night’s sleep, higher temperatures lead to increased moisture levels produced by perspiration. The maximum sweating rate that can be coped with by wool wadding is higher than both tested polyester and feather down, meaning that wool can diffuse a larger amount of moisture across an 8 hour period.

Overall, wool was found to let the most moisture escape and remain at a consistent optimum temperature when compared to feather/down and polyester duvets. Testing at two different temperatures also allowed the conclusion that these benefits are down to the fibre properties and structures of wool rather than the thickness of the duvets.

Key facts

  • Water vapour resistance in polyester and feather down duvets are around 92% and 125% greater than that of wool wadding when preconditioned at 70oC for 2 hours and are about 68% and 110% greater than that of wool wadding when pre-conditioned at 17oC and 40% for 2 hours.
  • Maximum sweating coping rate for wool is 600-640 gram/8 hours, Polyester is 420-440 gram/8 hours and feather down duvet is 360-390 gram /8 hours. Wool can cope with the most sweating.
  • Wadding samples were tested to eradicate the effects of extraneous variables such as the outer cover of a duvet

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