Wholesale Fabric Supplier Explains Water Resistant Fabrics

Posted: 2/19/2016

By: Terri Shadrix

Manufacturers know that fabrics have different degrees of resistance to water, mildew, rot and ultraviolet light. What may be harder to determine is which fabrics best support your product’s durability and lifespan targets. Before you buy large quantities of any water-resistant wholesale fabric, run down this checklist to ensure the best choice.

First some definitions of Water Resistance:

• Water-resistant: able to resist the penetration of water to some degree but not entirely.

• Water-repellent: not easily penetrated by water, especially as a result of being treated for such a purpose with a surface coating.

• Waterproof: impervious to water.

How Water Resistance Is Rated:

In most cases, waterproof ratings are determined by fabric producer themselves. Testing can be done either by independent laboratories or in-house.

The most common testing protocols in use involves the equivalent of placing a tube over the fabric and determining how high a column of water you can suspend over it before the fabric starts to leak. The higher the number, the more waterproof the fabric.

EXAMPLE: A square 1” x 1” tube is positioned over a piece of fabric. If at the point water begins to leak through, you had filled to a height of 10,000 mm (32.8 feet), that would classify it as a 10k or 10,000 mm fabric.

More advanced testing incorporates more exposures. Recently manufacturers have developed testing methods that involve adding the effects of wind. Also note that some manufacturers report waterproof ratings in PSI (Pounds per Square Inch) rather than millimeters. The conversion rate is 704 mm = 1 PSI.

Some sporting goods and other manufacturers have begun including this information on their product labels. Typical mid-range fabrics tend to have values of 5,000 mm of water resistance while the best materials have 20,000 mm.

Not all waterproof fabrics are used for clothing. The demand for stain and waterproof fabrics is also high in the upholstery industry, as well as the more obvious tent and awning industries.

Waterproof Rating Definitions Chart:

Remember that different labs may test or report differently, and may come up with different results even with two pieces of fabric from the exact same roll.

Before a major purchase consider running additional tests at outside labs to have a better sense of your fabrics true numbers.