The outer layer is the most familiar layer for both the amateur and the most outdoor savvy of enthusiasts. Otherwise known as the protective layer against the elements (snow, rain, wind, mud), the outer layer comprises of a mixture of different types of clothes which are focused on providing a balance between breathability and protection. These outer layer clothes include, hard shells, soft shells and insulated jackets.
Much like the mid layer, the outer layer needs to maintain insulation and be breathable, however its main role is to protect you physically from the environment like an outer skin. There is a large variety of different materials available for outer layer based clothing and normally these products include a waterproof hoodie (bonus if removable).
Hard shells are the most common types of outer layer that are available. These clothes are generally waterproof and provide a laminate layer that protects you against elements of all seasons. It is worth looking into how seams are insulated and making sure that zips and other enclosures are waterproof. Great examples of good hard shell jackets would be relative to 2 laminate fabrics and of course Gore Tex materials as they are both very breathable and resistant to the elements.
Soft Shell clothing is also another common outer layer (which is also used as a mid layer), however they are generally not waterproof and sometimes not as wind resistant either. One great feature of soft shell jackets are that they are very comfortable, stretchy and breathable (definitely worthy of being a mid layer clothing choice). A common misconception is that DWR (durable water repellent) coating methods will make not fully waterproof fabrics… waterproof. This is not the case as DWR is meant to be used on fabrics that are waterproof and assist in aiding the breathability of the fabrics from the inside.
Another outer layer that is best used to combat extreme weather is the insulation jacket. Insulated jackets provide additional insulation using extra material on the inside. Make sure that the combination of layers does not create too much insulation for the climate’s temperature as it will cause the body to overheat.