Most parents dress babies too warmly. It feels protective, but overheating is both a common cause of restless sleep and a recognised safe-sleep risk factor.
The target room temperature is roughly 16 to 20°C. In hot climates where that is not achievable, cooling the room and dressing down matters more than adding layers.
A simple layering guide:
| Room temp | Suggested layers | |---|---| | 24-27°C | Short-sleeve bodysuit, or nappy only in very warm rooms, light sleep sack | | 21-23°C | Short-sleeve bodysuit + light sleep sack | | 18-20°C | Long-sleeve bodysuit + medium sleep sack | | 16-17°C | Long-sleeve bodysuit + footed sleepsuit + warmer sleep sack |
A useful rule of thumb: dress your baby in one more thin layer than you are comfortable in, and count the sleep sack as a layer.
How to check you got it right. Feel the back of the neck or the chest — not the hands or feet, which run cool in babies as a matter of normal circulation and tell you nothing. Skin should feel warm and dry. Damp hair, a sweaty neck, flushed cheeks or rapid breathing all mean too warm. Cool chest means add a layer.
Safe sleep basics that override everything above:
- Always on the back, on a firm flat surface, in their own clear sleep space.
- No loose blankets, pillows, bumpers, positioners or soft toys in the cot. A sleep sack replaces blankets precisely because it cannot cover the face.
- No hats indoors. Babies release heat through the head.
- Never cover the face or head, and keep the cot away from radiators and direct sun.
On swaddling. It can help young newborns settle by reproducing the containment of the womb. Keep it firm across the chest but loose around the hips, never over the face, and stop swaddling completely at the first sign of rolling — usually somewhere around two to four months. A swaddled baby who rolls onto their front cannot push themselves back up.
In hot climates, prioritise cooling the room: close curtains during the day, use a fan positioned to circulate air rather than blow directly on the baby, and dress down to a single light layer. Air conditioning is fine; just avoid a direct draught on the cot and watch that the room does not swing cold overnight.
If your baby seems persistently sweaty, or persistently cold despite layers, mention it to your pediatrician.