Do Radiator Covers Reduce Heat Output? and how do they work?

A radiator cover reduces heat output by only a small amount. A well-designed one (with expertly made Fretwork) can even push warm air out into the room more effectively. There are even ways you can make your radiator more effective.

A radiator works by turning hot water (or steam) from a boiler into thermal energy. As the hot fluid flows through the unit, it heats the metal casing. This heat transfers into the surrounding room through two processes: convection (warming the air) and radiation (warming objects and people directly).
The whole cycle is, Heat Transfer, Convection, Air Circulation, Radiation.

  • Heat Transfer: A boiler heats water, which travels through pipes and into the radiator.
  • Convection: As the metal radiator gets hot, it warms the cold air sitting directly next to it. As this air gets warmer, it becomes less dense and rises toward the ceiling.
  • Air Circulation: As the warm air rises, it pushes cooler air down to the floor, which then flows toward the radiator to be heated in a continuous loop. This accounts for about 80% of the room’s warmth.
  • Radiation: The remaining 20% of the heat is emitted as infrared heat rays. This projects heat directly onto you and the furniture in the room rather than just warming the air.

Why do Radiator covers affect this?

  • Ventilation is Key: Radiators heat a room by drawing in cool air from the floor, warming it, and releasing it at the top. Covers with open grilles at the front promote healthy air circulation, which is why Detailed fretwork and clear open panels are the perfect balance between style and heat.
  • Material: Lightweight materials like metal grilles or mesh conduct and release heat into the room much better than thick, solid wood. In our products we use high quality breathable MDF  with clear open panels and beautiful fretwork which is only 6mm so it gives you the best of both worlds.
  • Thermostatic Radiator Valves (TRVs): If your thermostat is hidden inside a closed cover, it will read the warm air inside the box rather than the actual room temperature, so it’s always best to design your custom bespoke furniture with that in mind which is another reason you have your Radiator cover designed to the millimetre by you, made by us!.

Do Radiator Covers Reduce Heat Output?

  • Short Answer: Yes a very small amount but with the right design and the right placement you won’t be able to tell the difference while having those ugly chunks of metal out of the way covered in beautiful Fretwork in any colour of your choice.

Tips to help with Radiator heat while looking fantastic with a Jali Radiator cover :

  • Bleed them: Release trapped air so the radiator fills completely with hot water.
  • Clear the space: Keep any blockages and other furniture away from the front of the radiator cover fretwork, allow the heat to come out of every purposely designed hole in our panels.
  • Clean them: Dust and grime blocking the metal will block heat.
  • Add Reflective Panels: The Energy Saving Trust highly recommends adding radiator reflector panels behind your radiators. This foil bounces heat back into your room instead of letting it soak into your wall.

Interesting Fact: did you know if you paint your radiator black it can increase it’s heat output?
Reasons: Black is the the best colour for radiating heat. Having bare shiny metal radiators which are unpainted can cause you to lose up to 15% heat!