Why Wool Is the Best Thing to Sleep Under in Warm Weather

Sleeping in wool in summer? Yes, really

Here’s something that always surprises people: at The Wool Company, we sell more wool blankets in summer than in winter. Once you understand what wool actually does, it makes complete sense.

The trouble with a warm night

Warm nights and the wrong bedding make poor bedfellows. A synthetic blanket or throw doesn’t regulate temperature; it simply insulates. With nothing to buffer your body heat, you grow warmer and warmer until you throw the whole thing off, then cool down too far, only to find yourself dragging it back 30 minutes later. This flapping action can continue all night long. Man-made fibres can’t absorb moisture, so perspiration has nowhere to go, and you wake clammy and unsettled — tired before the day has even started.

Wool, linen and cotton: what each does best

Natural fibres aren't really rivals — they each suit a different job, and the best-made beds use several together.

• Wool — the regulator. The all-rounder for a warm, changeable night. Because it's hygroscopic, it buffers temperature both ways and keeps drawing moisture away as you sleep — which is why it works whether the night turns warm or cool.
• Linen — the cool one. Hollow flax fibres and an open weave make it the most breathable of the lot, shedding heat and moisture quickly with a cool hand-feel. Wonderful against the skin in summer, though it only cools and offers little warmth when it's cold.
• Cotton — the easy one. Soft, familiar and crisp to begin with, but it soaks up moisture and is slow to let it go, so for a warm or sweaty sleeper, it can turn damp and clammy.

The happy part is that they layer beautifully. A linen sheet over a wool mattress topper, with a wool blanket on top, gives you cool, breathable contact against the skin and wool's steady regulation through the whole night — the best of each, working together.

Wool’s natural quality: it regulates

Here’s the heart of it: wool regulates, where a synthetic simply insulates.

A man-made fibre can only trap heat. Once it’s warm under there, it stays warm, which is exactly why you end up throwing it off. Wool is cleverer. It’s nature’s technical fibre: each strand is naturally crimped and breathable, full of tiny air pockets that respond to your body and buffer it against changes in temperature; warmer when the night turns cool, cooler when it turns warm.

It manages moisture, too. Wool can absorb up to a third of its own weight in moisture and still feel dry to the touch, drawing perspiration away from your skin and releasing it into the air rather than leaving it to pool against you. That, more than anything, is the difference between waking comfortable and waking clammy.

Why wool works on a warm night

• Breathable — its structure lets air move, so heat doesn’t build up beneath the covers.
• Moisture-wicking — it carries perspiration away from the skin and dries quickly, so you stay dry rather than clammy.
• Naturally fresher — wool resists odour and stays fresher for longer between washes.
• Kind to sensitive skin — naturally breathable and dust-mite resistant, which many allergy-prone sleepers are grateful for.
• Renewable and biodegradable — it grows on the sheep’s back each year and returns to the soil at the end of its long life.

What the research says

In a University of Sydney sleep study carried out in warm conditions — a balmy 30°C — adults aged 50 to 70 fell asleep in around 12 minutes under wool, compared with roughly 22 minutes in polyester and 27 in cotton, and slept less fitfully through the night. As the study’s lead, Associate Professor Chin Moi Chow, describes it, wool helps hold you in “the thermal comfort zone” for longer.

Separately, research by British Wool and the International Wool Textile Organisation at Bangor University found wool to be the most effective of the common bedding fibres at regulating temperature and drawing moisture away as you sleep.

What our customers tell us

We could go on about the science, but our customers put it better:

“I swapped my old hollowfibre duvet for your lightweight merino throw. It’s transformed my sleep — no more night sweats.” — Neil T., Devon

“My husband’s restless legs have improved enormously since we changed from a duvet to wool blankets, and I sleep better as well.” — Harriet J., Telford

“So soft and beautiful. It keeps our little one cosy without overheating.” — Mrs Blake, Suffolk

Which wool blanket for summer?

For most warm nights, a medium-weight merino blanket is all you need over a sheet. Our Duchess Merino Blanket, woven by John Atkinson at Hainsworth and finished with a broad satin binding, is the core of our range and a bestseller for good reason: soft, beautifully made, and available in a range of colours, including the fresh Alaskan blue pictured here.

On the very warmest nights, a lightweight merino blanket keeps things even airier, and a fine merino throw folded over the foot of the bed is the perfect thing to pull up in the small hours, when the temperature dips before dawn. Buy once and buy well, and a good wool blanket will see you through many summers — and winters — to come.

Browse the full range: Wool Blankets & Throws.

Better for you, and for the world outside

Choosing wool is kind to more than your sleep. Unlike synthetic fibres — which are spun from oil and shed microplastics with every wash — wool comes from a renewable source, lasts for years, and quietly biodegrades when its life is finally over.

We write about this honestly, work in progress, and all, in The Sustainability of Wool Makes for a Clear Conscience and Is Wool a Sustainable Fibre?

Sleep shouldn’t be seasonal

Tired of waking up warm and restless? Let wool do what synthetic fabrics can’t.

Shop our wool blankets and throws →