What is DWR?

You've probably come across the abbreviation DWR. Probably in the combination DWR coating, DWR impregnation or DWR treatment. What exactly does it mean and why is it so widely used in the outdoor world? And do all these terms refer to the same phenomenon? We take a closer look in this blog.

Table of contents

• The how and what of DWR
• Where do we come across DWR impregnations?
• DWR and the environment
• Longevity and maintenance of DWR

The how and what of DWR

As mentioned, we usually encounter DWR in the word combinations DWR impregnation, DWR treatment and DWR coating. Basically, all these terms refer to the same phenomenon, but there are subtle differences that will become clear to you as you read this blog. But what phenomenon exactly does this DWR encompass? DWR stands for "Durable Water Repellent". Durable refers to DWR's lifespan (which is shorter than the use of the word durable suggests) and water-repellent to its actual effect. The effect of DWR is caused by an invisible impregnation of a textile fabric with different chemicals per manufacturer. The impregnation ultimately aims to make the fabric water-repellent. However, this does not mean that this makes the fabric waterproof. More on this in our blog on the differences between water-repellent, waterproof and water-resistant.

The effect of DWR is clearly visible on most hardshell jackets. It forms a kind of coating on the outer fabric of most hardshell jackets (hence the term DWR coating), on which droplets will form and slide off when rain falls. The latter is also known as wicking.

Where do we come across DWR impregnations?

On the upper fabric of jackets and trousers

Not for nothing did we just choose the example of a hardshell jacket. That is a common and probably also the best-known application of DWR. You will find DWR coating on almost all hardshell clothing (and lined clothing with a hardshell-like exterior). As mentioned, DWR does not make a garment waterproof, but it does make it water-repellent. The membrane of hardshell clothing ultimately makes the fabric waterproof, which you can read more about in our blog on waterproof membrane. However, the water-repellent effect of DWR ensures that the upper fabric does not become flooded with water, thus maintaining the breathability of the garment.

However, you won't only find a DWR coating on hardshell clothing. Other types of outdoor clothing made to protect you (to a certain extent) from wind and precipitation also often feature such a coating. Think of most softshell clothing, but also many insulation jackets. The function of DWR in these garments is purely to protect you from light precipitation.

On the upper fabric of sleeping bags

It's probably not the first or second option you were thinking of, but we often come across DWR coatings on the upper fabric of many sleeping bags from the more trekking and expedition-oriented segment as well. These do not aim to protect the sleeping bag's insulation material from precipitation, but rather from moisture in the form of morning and evening dew.

In combination with down

As you have read in our blog on down, the thermal properties of down reduce significantly once it becomes damp. Not surprisingly, over the years several manufacturers have come out with so-called "treated down" (or hydrophobic down). This is down that has undergone a kind of DWR treatment. The effect of such treatment is that the down absorbs less water and, once wet, dries more quickly. This treated down does not solve the problem of the poor thermal performance of wet down. But it is a noticeable improvement. Treated down can be found in down jackets as well as in sleeping bags.

Other DWR applications

There are plenty of other applications of DWR. As soon as it makes sense to make material that is not water-repellent make it so, DWR can be a possible solution. We see this clearly in some other examples of where we encounter DWR in the outdoor world: shoes, bags (and rain covers), umbrellas and tents.

DWR and the environment

So DWR clearly has added value in the outdoor world. Unfortunately, not everything surrounding the DWR phenomenon is positive. This is because the first generation of DWRs were composed of PFCs. You can read about the effect of PFCs on the environment and health in our blog on PFC's. For this blog, it suffices to know that harmful PFCs are not biodegradable. Thanks to the many DWR applications in outdoor clothing combined with the action of wind and precipitation, we find traces of these PFCs all over the world.

Fortunately, the industry is now increasingly aware of this problem and we are seeing more and more PFC-free DWRs appearing on the market. Most of the brands you come across on our website have now switched to this. However, there are still a few exceptions. This has to do with the fact that these new PFC-free DWRs wear out faster than the older generations of DWR and for a long time they also did not work as well. Thanks to innovations, the latter problem has almost been tackled, but the performance of the new generation DWRs still decreases relatively quickly. Particularly in the premium segment of hardshell clothing, you may therefore still come across PFC-containing DWRs. However, the brands where this applies all express the expectation that even these DWRs will be PFC-free within a few years. We also see this as a realistic development, as the problems with the faster wear of the new DWRs are certainly not insurmountable. More on this now.

Longevity and maintenance of DWR

As indicated earlier, the D of DWR stands for durable, which we can best translate to sustainable in the sense of long-lasting. However, the effect of DWR is certainly not permanent. In fact, a DWR coating already wears out simply by wearing it. Add to that the effect of, say, washing or friction from a backpack, and you can understand that DWR's effect diminishes significantly at some point. How to recognise this? It differs per type of product, of course, but with DWR coatings on clothing or tent fabrics, for example, you will see that small droplets no longer form on the upper fabric, which then bead off. The water forms much more large droplets and is also much more absorbed by the fabric. Fortunately, it is possible to maintain/renew most DWR impregnations. There are several maintenance products available for this purpose (depending on the type of product), which we can divide into two groups based on how they work.

Wash in

One way to restore the DWR is to wash it in. You can do this through your own washing machine with special detergents. Dt must all be done in a certain way. Pay close attention to the washing instructions of the particular product and the instructions of the specific detergent. The disadvantage of this repair method is that you have no influence on which parts of the product to be washed in are impregnated. In fact, this will be the same everywhere. So, for example, also on the inside of your jacket.

Inspray

When spraying in, you do have much more influence on this. This is because you literally spray the goodness on those parts where the original DWR leaves something to be desired. The disadvantage of this method is that you come much more into direct contact with the chemicals. So make sure you always do this spraying outside and do not accidentally inhale the spray.

For more detailed instructions on how to repair your DWR, please refer to our blog on maintaining technical garments. If you have any questions after reading this blog on Durable Water Reppellent, please do not hesitate to contact our customer service team. We will be happy to help you with all your questions.