How to Establish the Ideal Room Temperature

Balancing the temperature in your home can seem like a tricky operation once you get down to the details. You want to be warm enough to function in everyday clothes, but not so warm that you sweat going up the stairs. And on top of that, you want to spend as little as possible on gas or electricity to heat your home.

We’ve put together some of the questions you need answering about your home’s temperature, and how you can take control of it.

What is the ideal room temperature?

If you’ve ever had guests in your home who don’t take their coats off, you’ll already know that what’s comfortable for you might not be comfortable for others. People do get used to the temperature in their own homes, but the range of comfort is surprisingly small – it’s about 18–21 °C for the average living room.

Factors to take into consideration include:

• your age (elderly people and babies tend to need to be more comfortable closer to 21 °C)

• whether you’re sick or inactive (again, a higher temperature is generally required)

• how many layers of clothing you normally wear indoors

• what the temperature is like outside

• how well the room is ventilated

• how prone your home is to dampness

• personal preferences

(It’s worth pointing out that according to the WHO, temperatures in excess of 24 °C and below 12 °C carry cardiovascular risk, 12–16 °C is linked with respiratory risk, and at less than 9 °C, hypothermia can set in.)

Should temperature change from room to room?

Generally speaking, rooms that you use most often should be kept closer to your ideal temperature. The spare bedroom or study that hardly ever gets used can probably survive with lower temperatures.

Also, many people like to have their bedrooms a bit cooler. That’s partly because it can make sleeping easier, and partly because most of the time you spend in there you’re covered by a thick duvet. Obviously if you use your bedroom for recreation (normal for kids), it’s best with a higher temperature, but you may like to turn it down at night.

Bathrooms tend to be a little warmer than average because you’re often partially clothed and wet in there, and a bit more warmth will keep walls, floors and ceilings drier, which will help keep damp in check.

The best way to control temperature in different rooms is to fit thermostatic radiator valves (TRVs) to your radiators. They sense the temperature in the room and vary the flow of hot water into individual radiators when the heating is on. If you like one room cooler than others, simply turn that radiator down with the TRV.

It is possible to restrict the flow manually with the knobs on the ends of radiators, but that method is not as responsive as using TRVs – you’re simply making that radiator cooler than the others permanently (or at least until you open it up again).

Where should the thermostat be located?

The main thermostat in your home is simply a switch that tells the heating to turn on and off when it senses temperature changes. If the temperature is higher than your chosen setting, it will turn off; if it’s lower, it will turn on.

For that reason, it’s important that your thermostat is placed somewhere pretty average – usually a hallway, but often in the main living room.

If you place it somewhere cold, for example next to a door or open window, it will be fooled into thinking the temperature is colder than it actually is and switch on the heat. Next to your TV, over a radiator or in a small utility room, the thermostat will sense high temperature and turn on less often – if at all – for a typical 20 °C setting.

With fitted thermostats, you have no choice once it’s installed, but take care where you leave your portable wireless thermostat if you have one.

What role does a timer play?

A programmable timer overrides the thermostat entirely. If the timer is set to off, the heating won’t come on whatever temperature is in the home. If it’s on, the heating will only come on if the thermostat detects low temperature.

Typically, people program their timers to activate at 6 a.m. so the home is warm when they get up, then switch off at 9 a.m. when they leave for work, and finally switch on at 4 p.m. and stay on until 11 p.m. Weekends will have a different schedule, but timers can be programmed day by day.

Remember, the timer being in the “on” position doesn’t necessarily mean the heating is on. In summer, it might hardly come on at all, but the home should be at your preferred temperature when you’re in and awake.

What should I do if the home is empty for a while?

If you’re leaving your home for a few days, especially in the summer, you may as well switch off your heating altogether. If you’re going to be away for several weeks, however, it’s probably a good idea to leave your heating on (or timed to come on at certain hours of the day) with a lower temperature – say 16 °C. That way, if the temperature outside plunges, your home will be kept reasonably warm and you reduce the risk of damp or even frozen indoor pipes if it’s particularly severe weather. Letting the central heating turn on from time to time also stops sediment from blocking up valves, and can prevent moving parts from seizing up.

If you have a smart thermostat that’s connected to the internet, you’ll have much more control over the system, wherever you are in the world. You can react to low temperatures at home, and make sure the heating comes on an hour before you get back for a real warm welcome.

Will setting a higher temperature warm the house quicker?

Some people will turn up their central heating at the thermostat to warm up more quickly if they’ve just come in from the cold and switched it on. Unfortunately, it won’t make any difference. Hot water is hot water, and it won’t be any hotter because you’ve turned up the thermostat – it’ll just keep on warming the home past your comfort levels, and then take a long time to cool down again.