The coldest days will demand the additional insulation of a mid-layer: one between your base layer and the outer layer that is your final defence against the outside world. A stretchable, Roubaix-lined jersey, such as Endura’s FS-260-Pro Roubaix Jacket, or the recently tested dhb Vaeaon Zero jersey both have the fleece-lining that proves such an effective insulator.
Your choice of external layer will have much to do with your own personal thermostat, and prevailing conditions. If it’s windy, but not too cold, say nudging double digits, a ‘hardshell’ outer like a gilet maybe all that’s required to provide an extra defence against the wind or light rain. If, however, conditions are very cold, say, zero and below, but dry, a softshell jacket – heavier, but more insulating than a jersey – might be required. The RH+ Iceland Jacket is one to have fallen beneath the RCUK microscope this winter. Wet weather will demand an outer layer with different fabrics. Which brings us to…