Ever Evolving Waterproofing Technology
“Waterproofing” is an easily misunderstood
terminology and often confused with water
repellent and water-resistant technologies.
When one adds the term “Rain Proof ” to the
label, clearly a definition of terminology and
testing criteria is necessary to compare and
evaluate the marketing claims of activewear
brands and manufacturers. There is no
empirical data or standard testing on file
in determining either “water repellency” or
“water resistance”. Water Repellency simply
means the ability of a material to repel or
hinder the penetration of water and can be
used interchangeably with “water resistant”,
which refers vaguely to a protective coating
applied to a fabric that resists water for a
short time.
"DWR treated fabrics
can still trap up to
50% of their own
weight in water
between the fibers.
This is called ‘wet-
out.’ In addition, DWR
typically wears
off after a few
washings."
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Pedorthic Footcare Association | www.pedorthics.org
In contrast, waterproof fabric in accordance
to EN must demonstrate the strength to
withhold a static water column pressure at
minimum 1500mm. That definitively will
not allow rain water to penetrate the fabric.
However, at that level air permeability is
zero. Since the advent of plastic technologies
in the 20th century, the challenge has
been to develop fabrics that adhere to
the waterproof standards of laboratory
testing and combine those qualities with a
substantial degree of air permeability.
A common method used to protect fabric,
including laminates, from water absorption
is treatment with Durable Water Repellent,
commonly called DWR. However, even
the best DWR treated fabrics can still trap