How To Choose A Rain Jacket

There is nothing worse than being wet when you don’t want to be. Ideally, you want something reliable and portable, so that you’re always prepared. There’s an old saying that there’s no such thing as bad weather, just bad gear. Don’t hide from the rain this winter, instead purchase a rain jacket designed to keep you dry and protected when the clouds open up. Learn more below on how to choose the right rain jacket for you.


First Ascent Waterproof Jackets


Waterproof jackets offer the best performance in wet conditions. Designed with an outer shell impervious to water, these jackets feature fully taped seams and a Durable Water-Repellent (DWR) outer coating, to keep water from moving through the jacket’s surface, whilst still allowing perspiration to move out. Consider a waterproof garment for more extreme activities that will keep you outdoors for long periods of time - these are also usually warmer. Most waterproof jackets are also windproof.


These jackets are hydrophobic meaning that they are able to bead water off the jacket’s surface, keeping the inner dry during light moisture or rain conditions, but do not provide full waterproof coverage. Water-repellent garments have a waterproof membrane, combined with a DWR coating, but are not tape sealed. 

Water Resistant

In theory, if a jacket is water-resistant, it has been designed to have resistance against small amounts of water for a brief time. These jackets are typically coated with a light coating of DWR, which gives the garment a protective layer and assists in increasing the endurance of the jacket when exposed to moisture or light drizzle conditions. Water-resistant jackets are generally lightweight and are also very breathable, as well as wind-resistant.

How is a jacket’s waterproof column rating determined?

The water column rating of a jacket is tested by placing a glass tube over the surface of the fabric and measuring how much water (measured in millimetres) and what type of conditions the jacket can withstand. This measurement ranges from 2,000mm to 20,000mm. To put it into context, that’s the equivalent of a minimum of four draughts of beer versus the max amount of four kegs of beer (420 full draughts) that you’d have to spill on yourself in a short amount of time for it to penetrate your jacket.

2000 - 5000mm No resistance to some resistance to small amounts of moisture Drizzle/Snow
5000 - 8000mm Waterproof under drizzle or light pressure Light rain
9000 - 15000mm Waterproof under light to moderate pressure Moderate rain
16000-20000mm Waterproof under high-pressure Heavy Rain


First Ascent Waterproof & Water-resistant running jackets

What about breathability?

It is as important for a waterproof jacket to keep water out, as it is for sweat to escape, especially when being active. There’s nothing worse than that feeling of being wet with your clothes sticking to you. 

Breathability is measured by how much water vapour can be transferred through a square meter of fabric in 24 hours. The higher the number indicated, the more breathable the jacket or fabric will be. It’s tempting to say more is better, but the real answer depends on your level of activity.

<5000gr/m2/day Low
>5000gr/m2/day Moderate
>20000gr/m2/day High


Waterproof jackets are built using different membrane constructions; these constructions feature either a 3-layer, 2.5-layer, or 2-layer.

3-layer: the most robust, for harsher weather and environments. i.e a hike. Check out our Men’s Expedition Vertex Jacket or  Ladies Eb and Flow Rain Parka

2-layer: the least swishy (i.e. the quietest). Best for everyday wear. We recommend our AR-X Waterproof Running Jackets or Thunderclap Rain Jackets 

2.5 -layer: the lightest, best for general exercise as it's easily foldable and transportable. I.e. a run

3-in-1 Jacket

These jackets are versatile and suitable for year-round wear. Featuring a waterproof outer, with a detachable fleece inner, these jackets can be interconnected into all other garments which bear an interconnect mark. Example: Discovery 3-in-1 Jacket



Durable Water Repellent (DWR) is a coating that is incorporated in almost all First Ascent outerwear garments and assists with preventing a garment from becoming saturated by moisture or water, by beading water off the garment's surface.

TIP: Nikwax Tech Wash is used to treat rain jackets with a DWR coating, increasing the lifespan of the rain jacket.


Seam-sealed refers to the covering of the tiny holes made in the garment during the sewing process, such as by the zip or hem. Fully tape-sealed garments have been sealed by a waterproof tape overlay, to prevent water from leaking into the jacket. All First Ascent rainwear labelled as waterproof are fully seam-sealed.

Vapourtex Fabric

The First Ascent Vapourtex technology represents a high-performance and innovative fabric which offers superior waterproof protection. All garments bearing the Vapourtex mark feature an outer impervious to water, a seam-sealed inner and a minimum spec of 2000m WP/ 3000mm BR. The durable First Ascent Vapourtex range will keep you dry in wet conditions, while allowing perspiration to pass to the outer surface, providing ultimate comfort during all expeditions.

View our Rainwear Range.