Placing heat reflector foil behind radiators can reflect heat back into the room and stop it escaping through external walls, according to consumer advice from Which?.
The organisation shared the tip on its official TikTok channel, explaining how to "maximise your heat." It said the foil "allows the heat to be reflected back into the room" and is "particularly effective on external walls."
Low-cost installation and alternatives
Which? noted that radiator heat reflector foil can be bought for around £8 and is "padded and usually has an adhesive backing," which makes it "really easy to install."
Some people use tin foil as a cheaper alternative, but standard kitchen tin foil is not recommended because it can pose a fire hazard over time and degrades quickly. Safety experts and firefighters caution that kitchen foil can oxidise and degrade under the constant high temperatures of a radiator, creating a risk of smouldering or burning. Kitchen foil is also flimsy, crinkles easily, and lacks the proper insulation backing to be truly effective.
Where the foil works best
Reflector panels should only be placed on radiators fixed to uninsulated external walls, as this stops heat from escaping into the brickwork or outside air. There is no benefit to putting foil on internal walls between rooms, because any heat absorbed by an internal wall stays inside the home anyway.
If a home already has modern cavity wall insulation or foil-backed plasterboard, radiator panels will not make a noticeable difference.
Public reaction to the hack
In the comments on the TikTok video, one person said they had been "doing this for years" and that others should "definitely try it" because it is a great hack. Another asked whether it "really works," and someone responded: "Yes, how much depends on a few factors, like how much insulation is in the wall."
