Why do I wake up sweating at night?

Night sweats can be caused by a bedroom that's too warm (above 20°C), too many blankets, memory foam mattresses trapping heat, alcohol consumption before bed, or medical conditions. Try lowering the room temperature by 2-3°C, switching to breathable bedding, and avoiding alcohol within 3 hours of sleep.

Is it unhealthy to sleep in a cold room?

Sleeping in a moderately cool room (15-18°C) is actually beneficial for sleep quality. However, extremely cold rooms (below 12°C) can disrupt sleep, cause muscle tension, and may be dangerous for elderly people or those with respiratory conditions. The key is cool, not cold.

Should I leave the heating on overnight?

Generally, no. Your body temperature naturally drops during sleep, and a cool room supports this process. Set heating to turn off 30-60 minutes before bed, or reduce to a minimum overnight setting (15-16°C). This also saves significantly on energy bills.

Do electric blankets affect sleep quality?

Electric blankets can help you fall asleep in a cold room, but leaving them on all night may disrupt deep sleep by preventing your body's natural temperature drop. Use them to warm the bed before sleep, then switch off. Modern blankets with timers are ideal for this.

What's the best duvet tog for Ireland?

For Irish bedrooms without heating, a 10.5-13.5 tog duvet suits autumn/winter. In heated bedrooms or summer, 4.5-7.5 tog is often enough. Consider an all-seasons duvet (two duvets that clip together) for year-round flexibility—popular in Ireland's variable climate.

Does sleeping with the window open help?

Fresh air circulation can improve sleep quality and reduce CO2 buildup. In Ireland's mild climate, cracking a window is often beneficial except in very cold or wet weather. Even a small opening provides ventilation without dramatically dropping room temperature.

My partner and I prefer different temperatures—what can we do?

Temperature preferences are very individual. Solutions include: separate duvets with different tog ratings, a mattress with different firmness/materials on each side (some foam types sleep warmer), a fan on one side of the bed, or layered bedding that one person can adjust without affecting the other.

Bedroom Temperature for Better Sleep

Temperature is one of the most important—yet often overlooked—factors affecting sleep quality. Research consistently shows that a cool bedroom promotes deeper, more restorative sleep. Here's what the science says and how to apply it in Irish homes.

The Science of Sleep Temperature

Your body temperature follows a natural circadian rhythm, dropping by about 1-2°C as you prepare for sleep. This temperature drop is a signal to your brain that it's time to rest, triggering the release of melatonin (the sleep hormone).

A bedroom that's too warm interferes with this natural cooling process, making it harder to fall asleep and reducing time spent in deep, restorative sleep stages. Conversely, a room that's too cold can cause discomfort and restlessness.

The Sweet Spot

Optimal bedroom temperature for most adults

16-18°C

(60-65°F)

This may feel surprisingly cool, especially for those used to heated bedrooms. However, studies from institutions including Harvard Medical School and the Sleep Foundation consistently find this range produces the best sleep outcomes for most adults.

Recommended Temperatures by Age Group

While 16-18°C is ideal for most adults, different age groups have varying needs:

Group	Ideal	Acceptable Range	Notes
Adults	16-18°C	15-19°C	Cooler is generally better for deep sleep
Elderly (65+)	18-20°C	17-21°C	Slightly warmer to maintain circulation
Infants (0-12 months)	18-20°C	16-20°C	Critical—overheating increases SIDS risk
Children (1-12 years)	17-19°C	16-20°C	Similar to adults, monitor for comfort

Important: Infant Safety

For babies, maintaining a room temperature of 16-20°C is critical. Overheating is a known risk factor for Sudden Infant Death Syndrome (SIDS). Use a room thermometer and dress babies in appropriate layers rather than relying on heavy blankets.

Irish Climate Considerations

Ireland's temperate maritime climate presents unique considerations for bedroom temperature management:

Mild Winters

Irish winters rarely drop below freezing for extended periods. This means achieving the ideal 16-18°C bedroom is often possible without excessive heating—or any heating at all in well-insulated homes.

Many Irish homes are actually over-heated at night, especially those with oil or gas central heating left on overnight.

High Humidity

Ireland's humidity levels (often 70-90% outdoors) can make bedrooms feel colder than the thermometer suggests. Humidity also affects how we perceive temperature and can lead to dampness issues.

Keep bedroom humidity between 40-60% for optimal comfort. A dehumidifier can help in persistently damp rooms.

Older Housing Stock

Many Irish homes, particularly those built before 2000, have poor insulation. This can lead to rapid heat loss and cold bedrooms in winter, or conversely, reliance on overnight heating that makes rooms too warm.

Consider upgrading insulation or using draught excluders. Layer bedding rather than increasing heating.

Summer Warmth

While Ireland rarely experiences extreme heat, summer nights can occasionally exceed comfortable sleeping temperatures (above 20°C), particularly in south-facing or poorly ventilated bedrooms.

Blackout curtains help keep rooms cool during long summer days. Open windows in the evening to cool the space.

Seasonal Temperature Tips

Winter (Nov-Feb)

•Set bedroom radiator lower than living areas
•Use a programmable thermostat to reduce heating at night
•Layer blankets rather than cranking up the heat
•Consider a hot water bottle to warm the bed before sleep
•Keep bedroom door closed to maintain temperature

Summer (Jun-Aug)

•Open windows in the evening to cool the room
•Use lighter tog duvets (4.5 tog or less)
•Consider a fan for air circulation
•Keep curtains/blinds closed during hot afternoons
•Sleep with minimal bedding if needed

Spring/Autumn

•Adjust bedding weight as temperatures fluctuate
•Ventilate the room daily to manage humidity
•Be prepared for overnight temperature drops
•Use a 10.5 tog duvet for versatility
•Monitor humidity levels (40-60% ideal)

Practical Tips for Temperature Control

Use a Programmable Thermostat

Set heating to reduce automatically 30-60 minutes before bedtime. A gradual temperature drop mimics natural conditions and saves energy. Many modern thermostats can be controlled via smartphone for easy adjustment.

Get a Bedroom Thermometer

Our perception of temperature is subjective and often inaccurate. A simple digital thermometer (€10-€20) lets you know the actual temperature. Place it away from radiators and direct sunlight for accurate readings.

Layer Your Bedding

Rather than adjusting room temperature, use layers you can add or remove. A sheet, light blanket, and duvet give you flexibility. This is especially useful when sharing a bed with someone who prefers different warmth levels.

Consider Your Mattress

Memory foam mattresses retain more heat than innerspring or latex options. If you sleep hot, consider a hybrid with pocket springs for better airflow, or use a cooling mattress topper. Breathable bedding materials (cotton, linen, bamboo) also help regulate temperature.

Ventilate Daily

Open windows for 10-15 minutes each day to refresh air and reduce humidity. In Ireland's damp climate, this helps prevent condensation and maintains healthier indoor air quality. Even a brief airing makes a noticeable difference.

Energy-Saving Heating Tips

Maintaining cooler bedroom temperatures isn't just better for sleep—it's also better for your energy bills. Here's how to save money while sleeping better:

€Turn bedroom radiators to low or off: Heat other rooms for evening comfort, but let the bedroom stay cool. Close the bedroom door to maintain the temperature difference.
€Reduce thermostat by 1°C: According to Gas Networks Ireland, reducing your thermostat by just 1°C can cut heating bills by up to 10% without noticeably affecting comfort.
€Use thermostatic radiator valves (TRVs): These allow you to set different temperatures for each room. Set bedrooms lower than living spaces.
€Don't heat empty bedrooms: If guest rooms aren't in use, keep radiators off or on the frost setting to save energy.
€Invest in better bedding: A quality duvet and mattress topper can keep you warm in a cooler room, reducing the need for heating.

Frequently Asked Questions

The Bottom Line

The ideal bedroom temperature for most adults is 16-18°C—cooler than many people expect. In Ireland's temperate climate, this is achievable most of the year without excessive heating, making it both sleep-friendly and energy-efficient.

If your bedroom currently runs warmer, try gradually reducing the temperature by 1°C per week until you reach the optimal range. Combine this with appropriate bedding and you'll likely notice improved sleep quality within days.

Remember: your body needs to cool down to sleep well. A slightly cool bedroom supports this natural process, leading to deeper sleep and more refreshed mornings.