Cut and fit reflective foil behind a radiator to stop heat escaping into the wall, in under an hour.
RF-01Turn off the radiator and let it coolTurn the thermostatic valve on the radiator to off, or turn off the heating at the boiler or programmer. Wait at least an hour so the radiator and pipes are cool to the touch before you start. Working on a cold radiator is far more comfortable and stops you burning your hands when you reach behind it.
RF-02Clear the area and check the wall behind the radiatorMove any furniture, rugs or curtains out of the way so you can kneel or reach behind the radiator easily. Look at the wall behind it — brush away any loose dust, cobwebs or flaking paint with a dry cloth. The foil needs a reasonably clean, dry surface to sit flat against.
RF-03Measure the space behind the radiatorMeasure the width and height of the wall area hidden behind the radiator, from just below the top pipe connections down to just above the skirting or floor. Add about 20mm all round so the foil covers the full area without gaps. Write the measurements down before you cut anything.
RF-04Cut the foil to sizeUnroll the radiator reflector foil on a flat surface, shiny side down, and mark your measurements with a pencil. Cut it to size with a utility knife against a straight edge, or with sharp scissors if the foil is thin. Cut it slightly smaller than the gap if your radiator brackets sit close to the wall, so it slides in easily.
RF-05Fit the foil with the shiny side facing the radiatorSlide the foil down behind the radiator, between the pipes and wall brackets, with the shiny side facing outward towards the radiator, not the wall. This is what reflects heat back into the room instead of letting it soak into the brick or plasterboard. Some foils have a self-adhesive backing — if not, use small strips of double-sided tape to hold the top corners against the wall.
RF-06Check the foil sits flat and doesn't touch the pipesLook behind the radiator and check the foil lies flat against the wall with no bulges or gaps at the edges. Make sure it doesn't press against any hot pipework, as this can scorch or curl thin foil over time. Trim any edges that poke out from behind the radiator.
RF-07Turn the heating back on and tidy upTurn the radiator valve and heating back on and let it warm up as normal. Check after 20 to 30 minutes that the foil hasn't shifted or come loose from the heat. Put any furniture back and dispose of foil offcuts.
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