· 6 min read
Sleeping in a fleece onesie: warmth, sizing and care
Sleeping in a fleece onesie: the right bedroom temperature, how to avoid overheating, which size to choose and how to look after it.
- fleece onesie for sleeping
- adult fleece onesie
- womens fleece onesie
- mens fleece onesie
Sleeping in a fleece onesie is a good idea when your bedroom is cool and you lighten your duvet to match. In a room heated to 21 °C with a winter duvet, it's the opposite: you're likely to get too hot. This article covers bedroom temperature, sweating, the hood, sizing and care, with two styles from the shop: the Family Fleece Onesie and the Cable Knit Teddy Bear Onesie.
Sleeping in a fleece onesie: at what temperature?
A fleece onesie suits a cool bedroom, around 18–19 °C or below, provided you cut back on the duvet. France's National Institute of Sleep and Vigilance puts the ideal bedroom temperature at 18 to 19 °C and advises not going above 20 °C (INSV, “An ideal bedroom for a good night's sleep”, in French). France's national health insurance service, the Assurance Maladie, recommends not heating the bedroom above 18 to 20 °C and airing it (ameli.fr, “How to sleep better as an adult”, in French).
That's exactly what the onesie is for: keeping things cool without shivering. It covers your whole body in a single piece, so there's no top riding up and no bare back when you turn over. That means you can turn the bedroom radiator down, an idea we explore in our article on heating less without feeling cold.
Photo: 247homerescue / Wikimedia Commons (CC0)
The trap is piling it all on: a thick onesie, a winter duvet and a radiator set as high as in the living room. A few pointers:
- Bedroom below 18 °C: fleece onesie plus a light duvet or a throw.
- Bedroom at 18–19 °C: fleece onesie plus just a sheet, or a light duvet pushed down to your feet.
- Bedroom above 20 °C: thick fleece becomes too warm for the night. Keep it for the evening and switch to lighter pyjamas at bedtime.
The real drawback: sweating
Fleece holds in heat well but absorbs very little moisture. Both styles from the shop are made of 100% polyester fleece flannel, a synthetic fibre that doesn't soak up sweat the way cotton does. If you get too hot at night, that clammy feeling arrives quickly.
Photo: Rico Cilliers and colormass / Wikimedia Commons (CC0)
Three simple adjustments limit the problem:
- Open the zip. Both onesies fasten with a full-length zip: pulling it down to your breastbone is often enough to let the heat out without taking everything off.
- Wear a cotton T-shirt underneath. It absorbs moisture against your skin while the fleece keeps you warm on top.
- Lighten your bedding before you go to bed, not in the middle of the night.
If you still sweat, a fleece onesie isn't right for your nights. Cotton flannel, which breathes better, is compared with other fabrics in our guide to fleece, flannel, cotton or sherpa.
Hood, ears, pocket: what gets in the way at night
To sleep, fold the hood back. Hooded animal onesies are designed for the sofa: the hood warms your head, twists when you turn over, and the stitched-on ears make a lump on the pillow.
On the Family Fleece Onesie, the hood carries the animal's ears (panda, ginger tiger, brown bear, dinosaur or capybara) and a paw is appliquéd on the front pouch pocket.
The Cable Knit Teddy Bear Onesie has a thick knit in chunky ribs, described as “closer to a throw blanket than a sweatshirt”. Its wide legs fall to the floor: very comfortable on the sofa, less practical at night if you get up often, as the hem can catch under your foot on the stairs. Turn the legs up with a cuff.
What size fleece onesie for sleeping?
Take the size that matches your height, without going up a size “to be comfortable”. A onesie that's too big bunches up under your back and trails on the floor. The Family Fleece Onesie gives a height and weight for each size:
| Size | Height | Weight |
|---|---|---|
| Women S | 145 to 155 cm | 33 to 43 kg |
| Women M | 155 to 160 cm | 40 to 50 kg |
| Women L | 160 to 168 cm | 50 to 60 kg |
| Women XL | 160 to 168 cm | 60 to 70 kg |
| Men L | 165 to 172 cm | 63 to 69 kg |
| Men XL | 170 to 175 cm | 70 to 79 kg |
| Men XXL | 175 to 180 cm | 80 to 90 kg |
| Men 3XL | 180 to 185 cm | 90 to 100 kg |
Women L and XL cover the same height range: use your weight to decide between them. Each item is a single onesie, to be added size by size if you're kitting out several people.
The Cable Knit Teddy Bear Onesie is chosen differently: its product page gives the garment's measurements laid flat (chest from 108 cm in S to 122 cm in XL, total length from 143 to 146 cm) and describes a relaxed fit, so take your usual size.
To measure your height properly, follow our guide to choosing the right size of adult onesie.
What about children?
If your child sleeps in a fleece onesie, put the hood down and don't add extra covers. The Family Fleece Onesie comes in kids' sizes, from Kids 8 (90 to 105 cm) to Kids 16 (135 to 145 cm). The Cable Knit Teddy Bear Onesie only comes in adult sizes.
For little ones, France's Assurance Maladie advises against piling on layers of clothing and suggests checking, with a hand on the back of the neck, that the child isn't too hot: a damp neck means they're overdressed (ameli.fr, “How to put a baby to bed safely”, in French). A baby sleeps in a baby sleeping bag suited to their size, with no duvet or blanket, and not in a hooded onesie.
For matching parent-and-child outfits, see also our article on matching family Christmas pyjamas.
Care and safety
Machine wash the onesie at 30 °C on a delicate cycle, then air dry. That's the instruction on both product pages. For the cable knit, the page adds that the tumble dryer flattens the cables. Washed inside out and without fabric softener, fleece stays soft for longer: the details are in how to wash and care for fleece pyjamas.
Keep a roomy polyester onesie well away from flames: a candle on the bedside table, an open fire, a portable heater. The London Fire Brigade recommends keeping candles away from anything that can catch fire, clothing included, and putting them out before going to bed (London Fire Brigade, Candles).
In a nutshell
Sleeping in a fleece onesie works well in a bedroom at 18–19 °C, the temperature recommended by the INSV, as long as you lighten the duvet, fold the hood back and open the zip if you get warm. Choose your size by your height, without sizing up. If you're still torn between a onesie and two-piece pyjamas, our comparison of onesie or Monster Pyjamas for winter will help. You'll find the styles on the Family Fleece Onesie page, the Cable Knit Teddy Bear Onesie page, and in the shop.
Cover photo: Liz Lawley / Wikimedia Commons (CC BY-SA 2.0)