With storm season in full bluster, the need for dependable raingear develops a greater sense of urgency. If you’re shopping for a new rain jacket, you’ll quickly encounter a trio of seemingly interchangeable terms: water resistant, waterproof and water repellent. Is there really a difference between them?
Spoiler alert: “Waterproof” beats “water resistant” and “waterproof/breathable” will make you the driest of them all.
The technology in a jacket can be incredibly sophisticated. For an in-depth discussion of the subject, read our Expert Advice article: How Does Raingear Work? Here we’ll touch upon a handful of key concepts.
The preceding trio of water words do indeed mean different things, and if you want to know which jacket to wear based on your area’s weather forecast, it’s important to understand the distinctions between them. Essentially, water resistant and waterproof designate the degree to which rain is kept from getting through a jacket, while water repellent refers to an extra coating that improves any rain jacket’s performance (waterproof, included).
Water resistant is a lower level of rain protection
In theory, any fabric between you and falling rain will keep some water from reaching your skin, making it at least partially water resistant—and a surprising variety of jackets list water resistance as a feature. Assuming a jacket’s outer surface isn’t some absorbent material like cotton, it likely could handle a light drizzle. If you’re out for an extended time in the rain, or the intensity of that rain increases, though, you’re going to get wet.
Waterproof is the highest level of rain protection
If you want a jacket that can stand up to serious rainfall, then the technology game also gets serious. To achieve a truly waterproof fabric, jacket brands experiment with a seemingly infinite variety of outward-facing fabrics, as well as high-tech laminates or coatings in layered constructions.
From a lab-results perspective, a fabric is considered waterproof when it reaches a certain level of water resistance. But there’s no agreed-upon industry standard for this value, so you have to trust a brand’s claim that a fabric is waterproof. If you trust the brand, you can probably trust the designation, but you won’t be able to easily compare levels of “waterproofness” between brands.
(It’s also worth noting that, “waterproof” means something else for other types of gear—things that might get submerged, like a watch or a camera. For those types of items, a whole different set of tests and test standards come into play.)
What about “waterproof/breathable” jackets?
If the only goal is keeping rain out, then one could simply fashion a plastic bag into a jacket. The minute you exert yourself, though, your own sweat will make the jacket feel like a sauna. Inexpensive rain slickers and ponchos can shed rain—and meet waterproof standards—but you only want to wear one if you’re planning to sit or stand still.
In the end, it’s the combination of waterproof and breathable technologies that will keep you the driest if you’re headed outdoors during a serious rainstorm. Inventing this technology is what made Gore-Tex® fabric a household name. Today, you can find dozens of jackets with similar technologies. It’s worth noting that in general, the drier you want to be, the more you’ll need to spend.
Brands test breathability in the lab, too, again using a variety of methods and mandated results. The takeaway is the same, though: Comparing performance between brands isn’t possible, but, if you trust a brand, then you can trust its waterproof/breathable jacket has been rigorously tested.
Understanding water repellency
Durable Water Repellent (DWR) coatings are used on both water-resistant and waterproof jackets. The easiest way to explain what this coating does is to look at the surface of a new rain jacket during a light rain. When you see water drops bead up and roll off, you’re seeing water repellency in action.
A DWR coating doesn’t turn a water-resistant jacket into a waterproof one, but it does increase the level of water resistance of any jacket. It also prevents the surface layer of a waterproof/breathable jacket from getting saturated, enabling that jacket to operate at peak efficiency. When a jacket’s DWR coating eventually wears out, you can renew it to give your jacket back its full rain-protection mojo. Read Rainwear: Durable Water Repellent Care (DWR) to learn more.