Why DWR coating is important to your waterproof fabrics’ life cycle

August 14, 2023 | Read this in about 6 minutes

Whether you're an avid hiker, a seasoned mountaineer, or simply enjoy being in nature, investing in high-quality waterproof clothing is essential to staying comfortable and protected in unpredictable weather conditions. So how does the waterproof fabric in your jacket actually keep you dry? Beyond a membrane’s waterproof rating, a DWR treatment is another important component of creating a reliable waterproof breathable fabric. 

Investing in a high-grade product is just the first step in warding off dampness as you brave the elements. Understanding the importance of DWR coating and when to renew it will help you extend your gear’s life and performance so that it keeps you dry and moving through all your adventures. 


What is DWR coating? 

DWR coating – commonly known as durable water repellent finish – is an additional protective treatment that is applied to a garment’s face fabric to enhance its waterproof capabilities. Think of it as the first line of defense against rain and storms. 

When applied properly, DWR clothing treatment essentially acts as a topcoat that prevents water molecules from soaking into the garment’s face fabric. This means that the outer layer of the garment is protected from weather when a DWR finish is added, not just the membrane of waterproof technology, the inner lining, and the person inside of the garment. As an added bonus, DWR coating does not affect a garment’s breathability


How does DWR work?

There is some science to how DWR works. When water lands on a garment – or anything solid – it creates tension between the liquid and the landing surface. DWR increases the surface tension between water and a textile, creating a high contact angle that can be thought of as keeping the water molecules more upright rather than letting them spread out and soak into the material. 

When DWR is working at its most effective level of performance, it will cause moisture and water to noticeably bead up on a fabric’s surface. Those beads of water will roll off the garment as the wearer moves. 


Cleaning and washing your rain jacket 

Over time and with use, the effectiveness of DWR treatments may diminish. However, proper maintenance can help extend their lifespan and the lifespan of your garment:  

Regular cleaning: Clean your eVent garments regularly, as dirt and oils can affect the DWR performance. Follow the manufacturer's instructions for cleaning, but typically a gentle wash with a specialized detergent is recommended.  

Restoring DWR: If you notice that water is no longer beading up on the fabric's surface, it may be time to restore the DWR finishing. This can be done by applying a DWR-specific treatment, such as a spray or wash-in product. Follow the instructions provided with the product carefully.  

Heat activation: Some DWR treatments require heat activation to bond the treatment to the fabric effectively. This can be done by tumble-drying the garment on a low heat setting or using a warm iron. Always check the garment's care label before applying heat of any kind. 


Using DWR spray for jackets 

When you notice liquid making its way into the fabric of your waterproof jacket, there could be several causes. Natural abrasions and repeated use can create regular wear-and-tear on waterproof garments just like on other clothes. This wear-and-tear can lead to patches where DWR wears off over time. Luckily, applying a new coat of DWR is easy. 

Refer to the product care label sewn into the garment for specific directions for renewing and reapplying DWR coating. These will usually include specific recommendations for DWR replenishment products as well as any other needs to complete the process. Typically, manufacturers recommend washing any waterproof jacket with a special technical supplement prior to the DWR treatment, which usually involves spraying on or washing in the new DWR treatment. 

If your waterproof gear does not have a loop label sewn in, you can often find care instructions and recommendations on the product manufacturer’s website. 


DWR and sustainability 

As textiles have evolved and companies like eVent fabrics have become more environmentally conscious to focus on long-term eco-friendliness, waterproof breathable fabrics featuring sustainable materials have become more common product offerings. Regular DWR wash treatments are especially important for these garments as they help extend and revive the product’s longevity and waterproofness, ensuring your gear continues to meet your performance standards and personal needs. Many c0 DWR, pfc-free DWR restoring washes are available for consumer purchase for those who want to match a planet-positive treatment to their planet-positive rainwear. 


DWR fabric care 

A majority of outerwear products available for retail purchase are treated with a factory-applied DWR coating before being sold for consumer use. However, a DWR finish will gradually degrade over time and become less effective. 

To test a garment’s DWR finish, simply spray or splash a light amount of water onto the garment and see whether the water is beading up or being absorbed by the fabric. If the fabric absorbs the water or ‘wets out,’ it’s time to replenish the DWR coating. 

Consumers can purchase at-home DWR coating sprays in order to extend the life and effectiveness of garments featuring waterproof fabric. The eVent fabrics team recommends using a product like Nikwax® TX.Direct Wash-In or TX.Direct Spray-On for DWR clothing treatment. 

For more information about DWR spray for jackets and caring for garments with waterproof technology, review our fabric care guidelines. (Hint: DO NOT use an iron on DWR finish!) 


Maintaining a peak waterproof rating

DWR treatment is a crucial component in optimizing the performance of eVent waterproof fabrics. By enhancing water repellency, maintaining breathability, and providing stain resistance, DWR treatments ensure that your gear remains functional and comfortable in adverse weather conditions. 

Regularly washing and caring for your garments that feature waterproof breathable fabrics will benefit them in the long run, allowing you use them for an extended period of time. Once you notice abrasions and “leaky” spots in your waterproof technology, be sure to include a DWR wash or spray in the product’s cleaning cycle to ensure you can extend the lifespan of your product and enjoy it for years to come. Stay dry, stay comfortable, and embark on your outdoor adventures with confidence.