17°C is the ideal temperature for your bedroom at night – here’s how to reach it without increasing your bills

As we approach the winter months, the temperature has taken a drop. We’re especially feeling the effects at night, shivering under the sheets until we crank up the heating and our energy bills skyrocket. Where’s the sweet spot?

We spoke to two sleep experts and one energy expert to find the ideal temperature for your bedroom at night and how best to reach it without overshooting and waking up a sweaty mess. Here’s what they had to say.

What is the best temperature for your bedroom?

Dr Hana Patel, NHS GP and resident sleep expert at Time4Sleep says: ‘There’s a complex relationship between temperature and sleep quality, with overheated bedrooms often resulting in disrupted sleep. Even being slightly outside of the key temperature range of 15-23°C can make us more likely to wake up during the night and therefore reduce the amount of REM and slow-wave sleep we have, leaving us feeling fatigued. Most doctors recommend an ideal bedroom temperature of around 16-18°C.’

Around 17°C is the sweet spot. That might seem colder than you’d expect, but you need to consider that our bodies drop in core temperature, so says Dr Tim Mercer, NHS GP and GP Trainer, working with Opera Beds.

‘Falling asleep usually starts with a decrease in core body temperature, which is why it is easier to go to sleep in a cooler environment. Your core body temperature continues to decrease overnight, and your major sleep event, rapid eye movement (REM) sleep, occurs at your lowest core body temperature.’

With that in mind, the cooler temperatures outside should be a welcome addition in the bedroom.

Why your bedroom needs to be 17°C

Dr Patel says: ‘Overheating at night, even in winter, can diminish the time you spend in the restorative stages of sleep which are crucial for physical and mental recovery and cognitive function. It can also disrupt your circadian rhythm – your body’s internal clock – which further impacts your sleep quality.

‘Overheated bedrooms can cause continued restlessness throughout the night, resulting in delayed and disrupted sleep. Continuous heating can also lower the humidity in your bedroom, potentially leading to a dry throat and itchy eyes. Using a humidifier can support easier breathing overnight if your heating dries the air in your room.’

If you're a hot sleeper, cooling bedding can also help to lower your temperature. Cooling pillows, duvets and mattress protectors are all available and feel cold to the touch to help regulate your temperature.

Dr Patel highlights the importance of not being too cold either: ‘Your body needs to cool down before bed, but it should not be cold. If your room is too cold, your body will have to work harder to preserve warmth, usually through shivering and constricting blood vessels. This makes it harder to fall and stay asleep.’

What bedding should you use in autumn?

Dr Mercer continues: ‘As the seasons change, your bedding should change with them. I recommend switching from summer to autumn bedding when night-time temperatures consistently fall below around 15°C for 3 days in a row. At this point, a lightweight summer duvet may no longer provide enough insulation, particularly for older adults who can feel the cold more.

‘Rather than jumping straight to the thickest winter duvet, consider adding warmth gradually with breathable layers. This makes it easier to adjust your bedding as temperatures fluctuate and helps prevent the bedroom from becoming too hot overnight.’

An all-season duvet might be ideal in this case because it comes with two separate layers that you can use separately or pin together. One layer is generally thinner, at around 3.5-4.5 tog and the other is thicker at around 7-9 tog. You can mix and match to suit your sleeping style.

Different fillings feature different qualities, so you need to buy what works best for you. Down and wool will insulate well while being breathable, however they’re generally more expensive. Synthetic is cheaper and is easier to wash and dry, but you’re more likely to overheat under it. Using the best duvet for you can give you a better night’s sleep and make you less reliant on your heating.

How to avoid overheating

Martyn Fowler, founder of Elite Renewables and expert in home heating systems says: ‘Start with the thermostat. If the bedroom is getting too warm, lower the temperature rather than opening a window while the heating is still running. If you have radiators, a thermostatic radiator valve is useful because you can keep the bedroom cooler than the rest of the house.

‘With a heat pump, I’d usually avoid big temperature changes. They work better with steadier settings, so a small reduction overnight often makes more sense than turning everything off and asking the system to heat the house up quickly in the morning.’

If you use the bedroom predominantly for sleeping, it makes sense to keep it cooler compared to the rest of the house. That would save you energy and make it easier to sleep at night, so it’s a win-win. Smart thermostats allow you to create zones for such a purpose, but simply turning down the heating in that room, closing doors and blocking draughts can create a similar effect.