Reflective foil behind radiators
Some of the heat from a radiator will heat up the wall on which it is mounted. If that wall is an outside wall, a lot of this heat will be conducted to the outside of the building and lost. Luckily, it is very cheap and simple to prevent this from happening, by placing reflective foil on the wall behind the radiator. Research in the UK has shown that almost any kind of reflective foil (even ordinary aluminium kitchen foil) can reduce this heat loss by 5%. Properly designed reflective panels, which combine reflective foil with a thin layer of insulation, can reduce the heat lost through walls by up to 18%.