Breathability can be achieved in one of two ways:

1. Coatings

A polyurethane coating is applied to the fabric.  This will allow water vapour to be transmitted through the molecular chain to the outside edge where external water, such as rain, is repelled.  This is referred to as a “Hydrophilic” coated fabric.

Hydrophilic means that the coated side of the fabric draws water through the coating.  Hydrophilic = Water-Loving.  Some hydrophilic-coated fabrics are also “Fluorocarbon” proofed to enable water droplets to ‘bead’ on the outside edge, and then literally run off.  This will prevent the fabric from ‘wetting out’.  If a garment ‘wets-out’, it will appear as though the water is soaking or saturating the fabric.  This can block the path of escaping water vapour.  Fluorocarbon is known as “Hydrophobic”, or water hating.

2. Membranes

Gore-Tex is the most widely used and globally recognised breathable, waterproof membrane.