Heating off at night? How warm your baby's room should be this winter

The heating goes off at 10, and by 3am the house is cold. You lean over the cot, touch your baby's hand, and it feels like ice. The instinct is to turn the heating back on, or pile on another blanket.

Usually you don't need to do either. The Lullaby Trust, the UK charity for safer baby sleep, says babies are safer a little cooler than too hot. Overheating raises the risk of sudden infant death syndrome (SIDS), so the warmth you add at 3am matters more than the cold you feel in their fingers.

Cold hands are normal

A baby's hands and feet usually feel cooler than the rest of them. That tells you very little.

To check properly, put your hand on their chest or the back of their neck.

• Warm and dry: no change needed.
• Hot or sweaty: they're too hot. Take off one or more layers of bedding or clothing.
• Chest feels cold: add a layer of clothing, or switch to a higher tog sleeping bag.

What the room should be

The Lullaby Trust recommends 16 to 20°C for the room your baby sleeps in. It is hard to guess, so a room thermometer near the cot is worth having. At that temperature, a lightweight, well fitting sleep bag or light bedding is comfortable.

The charity's winter advice opens with heating bills, and it is reassuring on this: it is rarely necessary to keep the heating on all night. An extra layer usually does it. If you do leave the heating on overnight, keep it low, and no higher than 20°C.

Adding warmth safely

If your baby is in a sleep bag, don't put a blanket on top. Add a layer of clothing underneath, or use a higher tog bag. Don't put one sleep bag inside another: two 1.0 tog bags do not make a 2.0 tog bag, because air trapped between the layers makes them warmer than either rating suggests. There is no single chart that matches tog to room temperature, since fabrics differ, so follow the tog guide from the bag's manufacturer.

If you use blankets, keep them lightweight and avoid thick, fleecy or padded blankets and duvets. Put your baby feet to foot, with their feet at the bottom of the cot, and tuck the blankets in no higher than their shoulders. One blanket folded in half counts as two.

Things to leave out:

• Hats indoors. Babies lose heat through their heads, so a hat can make them too hot.
• Hot water bottles anywhere your baby sleeps.
• Weighted sleep bags or blankets for babies under one.
• A cot next to a radiator. Move it away from heat sources, and point any portable heater away from your baby.

When it isn't about the room

A baby with a cold or a high temperature can feel warmer than usual. Dress them for the room as normal, and don't wrap them up more because they are unwell. If your baby has a fever or you are worried about them, call your GP or 111.

Tonight

Put a thermometer in the room before you go to bed. When you check on your baby later, skip the hands and feel the back of their neck.

All guidance here is from The Lullaby Trust's advice on room temperature, cold weather and dressing your baby for sleep. If you are the one lying awake in a cold bedroom, our piece on the best temperature for adult sleep covers that side.