With energy bills on the rise, many homeowners are looking for ways to reduce their costs. One common question is whether it’s okay to turn off radiators in unused rooms. Here is a look at the main considerations.
Quick Answer
The quick answer is yes, it is generally fine to turn off radiators in rooms that are not being used regularly. This can help reduce energy waste and lower heating bills. However, there are some important factors to keep in mind.
Key Considerations
Preventing Pipe Freezing
One of the main concerns with turning off radiators is the risk of pipes freezing, which can cause major water damage. The risk depends on several factors:
- How cold it gets – Areas with very cold winters are at higher risk.
- Pipe location – Pipes on external walls or in uninsulated spaces are more vulnerable.
- House insulation – Well-insulated homes maintain warmth better.
- Radiator location – Turning off upstairs radiators is riskier than downstairs.
To prevent freezing:
- Maintain low background heat in unused rooms. Experts recommend around 10°C.
- Keep doors open to allow some heat circulation.
- Insulate vulnerable pipes and external walls.
- Only turn radiators off when away for short periods, not whole winter.
Moisture Build-Up and Mold
Turning off radiators can also lead to excess moisture in unused rooms, which can cause mold growth. This happens because colder air can’t hold as much moisture. Key tips:
- Keep some ventilation in unused rooms by leaving windows open a crack.
- Open doors to allow air circulation.
- Occasionally turn radiators on and open windows to change the air and remove condensation.
- Use a dehumidifier to control moisture levels.
Boiler Function
Modern boilers and heating systems are designed to work most efficiently with a certain minimum heat load. Turning off too many radiators can cause:
- Boiler “short-cycling” – turning on and off frequently, wasting energy.
- Reduced boiler lifespan due to increased wear.
- Less even heat distribution in rooms still calling for heat.
To prevent issues:
- Don’t turn off more than 1/3 of home radiators.
- Maintain an even distribution of on/off radiators.
- Use thermostatic radiator valves to fine-tune room temperatures.
Best Practices
Based on the key factors, here are some best practices for turning off radiators in unused rooms:
- Only turn off 1-2 radiators maximum to avoid overburdening your boiler.
- Focus on rooms that are infrequently used – spare bedroom, basement, etc.
- Leave radiators on a lower setting vs. completely off.
- Make sure rooms don’t get below 10°C to avoid freezing.
- Keep doors open and maintain ventilation.
- Insulate pipes and walls if very cold.
- Use background heat and dehumidifiers to control moisture.
- Flip radiators back on periodically to circulate air.
Estimated Energy Savings
The potential energy and cost savings will depend on several factors:
- Size of room – Larger rooms offer more potential savings.
- Insulation – Better insulated homes lose less heat overall.
- Climate – Colder regions use more heating fuel.
- Fuel type – Electric heat is more expensive than gas.
- Boiler efficiency – Newer systems waste less heat.
Based on average UK home sizes and fuel prices, turning off 1-2 radiators can save around 5-15% on your annual heating bill. For the average home, this works out to:
| Fuel Type | Potential Annual Savings |
|---|---|
| Natural Gas | £80 – £150 |
| Heating Oil | £100 – £180 |
| Electric | £60 – £120 |
These estimates assume a well-insulated, average-sized home. Your actual savings could be higher or lower.
Considerations for Different Homes
Older, Poorly Insulated Homes
Turning off radiators in older, drafty homes can be riskier due to greater heat loss and freezing risk. Key tips:
- Avoid turning off more than 1 radiator.
- Prioritize insulating attic, walls, windows, and doors first.
- Upgrade to a modern, high-efficiency boiler.
- Only turn off radiators for short periods when away.
- Keep background heat on low temperature.
Newer, Well-Insulated Homes
Newer homes with better insulation can turn off more radiators safely. Recommendations include:
- Can turn off 2-3 radiators for longer periods.
- Insulate any vulnerable pipes.
- Install thermostatic radiator valves for better control.
- Use smart controls to turn radiators on/off automatically.
- Take advantage of savings by turning off more heat in unused rooms.
Large, Multi-Story Homes
Larger homes have more rooms to turn off radiators, but also greater risk of heat imbalances. Tips include:
- Strategically leave radiators on upstairs and downstairs for circulation.
- Close doors to avoid heating unused hallways.
- Insulate any rooms or pipes on external walls.
- Use multiple thermostats for better temperature control.
- Add radiator foil panels in unused rooms.
Conclusion
Turning off radiators in unused rooms can provide good energy savings, but should be done with care. The most important factors are preventing pipe freezing, controlling moisture, and maintaining enough heat load for your boiler. Follow the best practices outlined above to maximize savings while avoiding potential issues. Home insulation, boiler efficiency, thermostatic valves, and smart controls can all make it safer and easier to turn off radiators. With the right precautions, most homes can turn off 1-3 radiators safely and save 5-15% on heating costs.