Technical outdoor jackets: waterproof_ windproof and breathability explained
Modern technical outdoor jackets combine waterproof and windproof qualities with breathability_ thanks to advanced materials and constructions. The key properties_ from fully waterproof to water-repellent_ windproof and breathable_ are explained below_ as well as the technologies that enable this performance_ because does anyone really know the difference?
Waterproof vs water-repellent
A jacket is called waterproof if it keeps out precipitation completely_ no matter how long or hard it rains. This performance level is usually indicated by the water column: the higher this value (in millimetres)_ the better the rain resistance. Technical outdoor jackets often offer 10_000 mm or more_ while extreme expedition models reach 20_000-30_000 mm.
Water-repellent (also known as water-resistant) means that the outer fabric causes water to bead up. However_ with prolonged exposure_ moisture will eventually seep through. Such a material is fine in a short shower_ but will leak if it gets soaking wet.
Therefore_ advanced rain jackets combine a waterproof membrane with a durable_ water-repellent DWR coating on the outer layer. This coating ensures that raindrops roll off the fabric without penetrating the fibres. An important detail: such DWR-wear decreases due to dirt_ friction and washing_ and must therefore be regularly re-impregnated to remain effective.
Windproofness
Protection from wind is just as crucial_ as a harsh wind can quickly cool you down (windchill). A fully windproof jacket blocks the wind and prevents cold air from cooling the insulating layer under your clothing.
In practice_ a truly waterproof hardshell is automatically windproof as well. Such membranes let virtually no air through. Softshells_ on the other hand_ are often wind-resistant. They block 80 to 95 percent of the wind_ but are therefore not completely windproof.
Breathability
In addition to protection from the outside_ a good outdoor jacket must also stay dry from the inside. The breathability of a jacket is the capacity of the material to wick away perspiration in the form of vapour. Anyone who moves intensively in a non-breathable rain jacket will inevitably become clammy inside.
Therefore_ technical rain jackets use microporous membranes or coatings that allow water vapour to pass through_ but not the larger water droplets. This is often expressed in:
- MVTR value (Moisture Vapour Transmission Rate) : how many grams of water vapour per m² can escape in 24 hours. A value of 10_000 g/m²/24h or more is seen as highly breathable.
- RET value (Resistance to Evaporative Heat Transfer) : the resistance the material offers to vapour permeability. The lower the number_ the more breathable (RET < 6 = excellent_ 6–13 = good).
Tenson_s own MPC™ laminate also works according to this principle_ where rain beads off the surface while moisture from the body is transported outwards_ allowing the garment to “breathe” during intensive activities.
For very intensive efforts_ outdoor athletes often opt for a softshell instead of a hardshell. Such a jacket is usually only water-repellent_ but has a much higher breathability_ which prevents condensation.
Materials and technologies
There are two main ways to make a jacket both waterproof and breathable: via a separate membrane under the outer fabric (such as Gore-Tex®) or via a thin coating on the inside of the fabric. A microporous membrane is usually more durable_ but both techniques provide a windproof_ waterproof and breathable construction. In addition_ with good rain jackets_ all seams are taped (sealed with heat-sensitive tape) to prevent water from penetrating at those vulnerable points.
Furthermore_ details such as waterproof zips_ a well-fitting hood and ventilation zips under the arms provide extra protection and more wearing comfort. The end result is a functional outdoor jacket that is ready for all weather conditions_ without compromising on comfort. Whether choosing a hardshell for maximum protection or a softshell for breathability during intensive activities: the right jacket depends on the situation of use.
This article was produced in partnership with Tenson. For more information on Tenson_ visit the brand page.