Waterproof Clothing: Is It Really Waterproof? Decoding the Technology

Getting ready for your first trekking trip in the upcoming rainy season, when the weather turns unpredictable and sudden downpours can strike at any moment?

Many people assume that a "waterproof" label alone means a garment is completely water-resistant. In reality, the situation is far more complex, and waterproofing depends on the fabric construction, the surface coating, and the waterproof membrane inside.

In this article, Supersports will help you better understand the technology behind waterproof clothing and how to choose the product that best fits your needs.

What Is Waterproof Clothing? How Does It Work

Clothing that is water-resistant or waterproof (water-resistant or waterproof apparel) refers to products that are specially treated or constructed to keep water from soaking through while still letting body moisture escape during activity. Not all products are the same — some only protect against light rain, while others can withstand heavy downpours and harsh weather conditions. This technology is now most commonly applied to windbreakers, waterproof jackets, outdoor activity pants, trail running shoes, hiking shoes, and even some t-shirts or tank tops for running that get a surface treatment for light water resistance in drizzle.

To create waterproofing, brands typically combine two core technologies: the DWR water-repellent coating and the Waterproof Membrane.

Durable Water Repellent Coating (DWR)

DWR (Durable Water Repellent) is a chemical coating that increases the surface tension of the fabric, causing water to bead up into round droplets and roll off the surface instead of soaking in. This helps the garment resist getting wet in light rain and dry faster after contact with water. However, DWR is not a complete waterproofing layer on its own — it only supports the waterproof membrane underneath. DWR wears down over time, and when water no longer beads on the fabric surface but instead soaks in and spreads, that's a sign the DWR needs maintenance. In this case, you can wash the garment with a specialized cleaning solution, then tumble dry on low heat or use a warm iron to reactivate the coating.

Waterproof Membrane

If DWR is the outer layer of protection, the waterproof membrane is the core technology that determines the garment's actual waterproofing performance. This is an ultra-thin membrane laminated between fabric layers, with pores small enough to block liquid water droplets from entering, yet large enough to let body moisture (sweat) escape, keeping the wearer dry and breathable during outdoor activity.

Choosing Waterproof Clothing For Each Activity

Not every outdoor activity requires the same level of waterproofing — choosing the right one for your needs helps you save money while getting a product that actually performs when it matters:

Running

If you only run in the city or occasionally get caught in light rain, a garment with a DWR coating already meets your needs well — prioritize lightweight, breathable fabric over a high HH (Hydrostatic Head) rating.

Multi-Day Trekking, Hiking

Choose clothing with a genuine waterproof membrane, a waterproof rating of 10,000mm or higher, and seam-sealed construction so water can't seep through the stitching.

Trail Running

Compared to road running, trail running takes you onto routes where the weather can change at any moment — sunny skies can turn into heavy rain, thick fog, or cold wind just after a climb. In these situations, a good waterproof jacket helps keep your body warm, not just dry, since prolonged cold and wet conditions are a common cause of hypothermia in the mountains. Because of this risk, most ultra trail races classify a waterproof jacket as mandatory gear: UTMB requires it, and Vietnam Mountain Marathon or Vietnam Jungle Marathon also require runners to carry a waterproof jacket with a hood — failing to do so can result in time penalties or even disqualification.

Frequently Asked Questions

Is waterproof clothing 100% water-resistant?

No. Waterproof clothing only reduces water penetration to varying degrees; it doesn't guarantee 100% protection in every condition.

How is waterproof clothing different from a raincoat?

A raincoat prioritizes total waterproofing but tends to feel stuffy, while athletic waterproof clothing balances waterproofing with breathability, making it more comfortable during activity.

How do you wash waterproof clothing?

Wash gently in cool water, avoid fabric softener or harsh detergents, and follow the manufacturer's instructions to preserve the garment's waterproofing performance.

Is waterproof clothing hot to wear?

Today's trail-specific models are designed to improve moisture evaporation and support breathability during activity. However, in hot and humid conditions, wearers may still feel warmer compared to a regular running shirt, due to the protective construction and thicker material layers.

Do You Need To Buy Waterproof Gear Right From Your First Trekking Trip?

The answer depends on where and when you're going. If your trekking trip is a day hike, the weather is dry, and the route is easy, you don't necessarily need to invest in a waterproof jacket right away. On the other hand, if your trip spans multiple days, takes place during the rainy season, or covers an area with rapidly changing weather, quality waterproof clothing is a worthwhile investment — staying dry not only makes you more comfortable but also helps reduce the risk of heat loss and keeps you safer throughout the trip.

Does the DWR coating wear off after washing?

Yes, DWR gradually diminishes over time, but it can be restored using a dedicated re-waterproofing product.

You can test your DWR by spraying water on the garment: if the water beads up and rolls off, it's still working well; if it soaks into the fabric, the coating has weakened. The DWR layer doesn't reduce breathability since it only coats the individual fibers of the fabric.

To restore it, wash the garment according to the brand's instructions, then tumble dry on low heat for 15 minutes to reactivate the water-repellent coating.

Recommended Authentic Waterproof Clothing At Supersports

Columbia stands out with Omni-Tech™, a waterproof technology used across a wide range of outdoor apparel, which can be paired with sealed seams for added protection. At the premium tier, OutDry™ Extreme places the waterproof membrane on the outermost layer, helping to minimize the "wet-out" effect and eliminating the need for a traditional DWR surface coating. This makes it a strong choice for hiking or trail running in wet conditions.

Meanwhile, Nike focuses on DWR and Nike Repel technology across its running jackets, which cause water to bead up and slide off the surface. Products like the Nike Repel Miler Running Jacket are well-suited for running in light rain, thanks to their lightweight, packable design and breathable construction.

With Under Armour, UA Storm focuses on lightweight water resistance, causing water to bead up and slide off the surface while maintaining breathability. This technology appears on products like the Under Armour Outrun The Storm and Launch Lightweight Jacket , both suited for running in light rain.

Overall, Columbia Omni-Tech™ and OutDry™ Extreme are ideal when you need a dedicated waterproof outdoor jacket. Nike Repel is geared toward trail running and high-intensity activity, while Under Armour UA Storm suits lighter, everyday needs. When choosing, be sure to check the specific technology used on each product to find the right level of waterproofing for your actual activity.

At Supersports, you can easily find authentic sports brands in Vietnam along with a wide range of footwear and accessories to support outdoor activities such as running, hiking, and trekking.

Supersports is VIETNAM'S NO. 1 AUTHENTIC SPORTS FOOTWEAR, APPAREL, AND ACCESSORIES RETAILER AND DISTRIBUTOR. The brand is part of Central Retail Group — a leading retailer from Thailand.

Supersports operates a retail network carrying more than 30 well-known sports brands, including Nike, Adidas, Crocs, Puma, and more. Among these, Supersports is the official and exclusive distributor of Under Armour, HOKA, and Columbia. We are committed to bringing authentic, top-quality products to sports enthusiasts across Vietnam.