Softshell Jackets are designed for use outdoors as part of the layering system, and can be used alone, ideal for aerobic activity in light weather conditions if they are water repellent and highly breathable, or as an insulating layer under a 'hard shell' outer jacket.
Softshell Jackets can be worn in place of a fleece when you need more protection, and can be used in a variety of conditions. Despite most softshell jackets being weatherproofed, and able to shield you from minimal amounts of rain and wind via a DWR (Durable Water Repellent), softshell jackets are not designed for use in severe weather conditions unless theya re worn in conjunction with a hardshell, such as a waterproof jacket.
For their ability to be used in a variety of situations and environments, soft shell jackets are a cost effective purchase.
Softshell Jackets can be used in good weather on the hill or for use when you need more breathability than a hardshell waterproof.
Hard shell jackets are more rigid and waterproof, which makes them favourable for predicatble bad weather in the outdoors.
Because softshell jackets are designed to have higher levels of breathability and flexibility, whilst still offering more water and wind repelling qualities than a midlayer such as a fleece they are popular with walkers and climbers who need a close to the skin fit, with good breathability, and less weatherproofing.
The arms and body of a softshell are designed to be flexible and easy to move. An example of this is The North Face's 'Angel Wing Movement' technology, or the Berghaus Choktoi Pro Jacket, in which you can move your arms above your body without your clothing rising up during high activity.
Softshell Jackets can be created with an athletic or an alpine cut, and can be adjusted with the use of hem or drawcords so you can pull them close and keep the wind or rain out making them ideal for climbers who don't want a long cut that hinders their harness.
Softshell Jackets are easy to layer over, making them ideal for changeable weather. They also do not have a fabric construction which would cause them to 'rustle'.
Membranes can be used in order to make your soft shell waterproof or to achieve water repellency.
GORE-Tex is a well known membrane used in clothing, and water repellency is achieved by the use of a coating in the final process of manufacturing, which is known as a DWR treatment (Durable Water Repellency.)
These membranes consist of an extremely thin film containing microscopic pores that are large enough for body moisture to pass through, but small enough to keep water droplets out, whereas DWR coatings are added to the fabric after a laminate or membrane has been applied to form a protective wall from water droplets on the outer layer.
Windproof Coatings and Membranes (e.g GORE Windstopper) can also be applied to a garment to achieve windproofing.
To make a softshell windproof, they can be made with an expanded polytetrafluoroethylene (PTFE) membrane, known as a PTFE. This is laminated between the face fabric and the inner liner, resulting in a thicker, wind resistant fabric.
Typically, for windy conditions, manufacturers of softshell jackets also include fleece layers to counteract wind chills.
The downside of using any kind of thicker PTFE is the subsequent loss of breathability.
Most soft shells are windproof, and they typically use a membrane coating to achieve this, combined with a construction that shields the user from wind, such as toggles and drawstrings that pull the soft shell in close to the body.
Cuffs are typically ribbed to reduce the amount of open entry points for wind.
For active wear you should choose a soft shell with excellent levels of breathability, but for perceived bad weather, you should choose a garment with ‘good’ levels of breathability, which are likely to have thicker coatings or PU or PFTE to be more resistant to weather, but less breathable overall.