Your guide to
home heating & radiators
Discover how central heating works, understand radiator heat output and learn how to choose, position and control your radiators for a warmer, more efficient home.
1. How central heating works
A typical wet central heating system heats water in a boiler and circulates it through pipework to radiators around your home. The radiators release heat into the rooms and the cooled water returns to the boiler to be reheated, creating a continuous cycle.
Heats water and circulates it through the system.
Release heat into your rooms.
Heated water travels through the pipework.
Cooled water returns to be reheated.
2. Understanding radiator heat output
Radiators are rated by heat output, usually measured in BTUs (British Thermal Units) or watts. The higher the output, the more heat a radiator can release into a room under its rated conditions.
BTU/hr is a measure of heating power commonly used for radiator sizing in the UK.
Another measure of heat output. 1 watt equals approximately 3.412 BTU/hr.
The right size makes a difference
A radiator with the correct heat output helps keep your room comfortable. An undersized radiator may struggle to reach the desired temperature, while an oversized radiator may be unnecessarily large or expensive.
3. Choosing the right radiator
Different radiator styles can provide effective heating. Choose the design and heat output that suit your room.
Horizontal radiators
A classic choice, ideal for most rooms.
Vertical radiators
Great for narrow walls or limited space.
Column radiators
Timeless style with a range of heat outputs.
Electric radiators
Ideal for independent room heating and control.
4. Radiator placement
Where you position radiators can affect how effectively they heat a room. Good placement helps warm air circulate and reduces cold spots.
• On suitable external walls
• Beneath windows where appropriate
• With space for airflow
• Behind large furniture
• Inside enclosed cupboards
• Where airflow is restricted
Top tips
Allow space around the radiator for good airflow.
Avoid blocking radiators with furniture or thick curtains.
Use thermostatic radiator valves to help control room temperature.
Check the required heat output before choosing radiator dimensions.
5. Improving heating efficiency
A few simple steps can help your heating system work more efficiently, keeping your home warm while reducing unnecessary energy use.
Adjust the temperature in individual rooms.
Help radiators heat evenly throughout your home.
Reduce heat loss and lower your heating requirements.
Choose comfortable settings without overheating rooms.
Find the right radiator for your home
Use our BTU Calculator, explore our insulation advice and browse radiators to create a warmer, more comfortable home.