As bikepackers from the not-so-sunny north of the UK, we have always understood the importance of keeping your gear dry and protected. Anyone riding for long and far enough will experience unpredictable weather conditions; the last thing you need is for your gear to let you down. 

At Restrap we take pride in our innovation and commitment to durable, highly functional kit. But what does “waterproof” really mean when it comes to bags? What makes a product waterproof, and how can you as a rider ensure all of your kit stays dry all of the time?


First up; a product is only as waterproof as the fabric it uses. Even here though, it’s a little more complicated than that. A bin bag is waterproof, but you aren’t going to take it bikepacking. Our outer fabrics are not only waterproof but also highly durable. They’ll shed water on the day you buy them, but also after weeks in the saddle in demanding environments. To achieve this, we use a number of different technologies.

Polyurethane (PU) and Thermoplastic Polyurethane (TPU) Coated Materials: Enhancing durability and water resistance

Our bikepacking bags feature PU and TPU coated fabrics. While different in terms of look and feel, the end result is similar. These coatings create an impermeable, stretchy backing to the fabric, boosting water resistance and durability. In general, TPU coated fabrics are more durable, but heavier. PU coated fabrics work best when used in conjunction with a DWR coating (see below!). All of our ranges use PU coated fabrics as liners and outers. You’ll find TPU coated fabrics on our utility range.

Durable Water Repellent (DWR) Coating: Shedding water quickly

If you own a waterproof jacket, you’ll probably have heard of DWR. All of our PU fabrics are treated with DWR. This specialist treatment creates a hydrophobic coating to the fabric and helps water bead and roll off the bag quickly. 

X21 technical waterproof outer: Faster and lighter

Our race range uses X21 fabric, which is a lighter, PU laminated fabric. While it sheds weight, it keeps all of its durability and water-shedding properties.

PFAS-Free Materials: Sustainability and environmental responsibility

At Restrap, we believe in taking care of the places that we love. That's why we prioritise the use of PFAS-free materials wherever possible in our bikepacking gear. By eliminating potentially harmful chemicals, we not only protect the health of our customers but also minimise our impact on the environment. 


So the raw ingredients are waterproof… how do we make sure the final product is too?

Seams: Built to last, then sealed against the elements

It’s obvious when you think about it, but as soon as we stitch together two pieces of waterproof fabric, the thread holes introduce an opportunity for water to creep in. That's why we take the time to make sure all seams use a reinforced construction and we then seam-seal them in-house using high quality tapes and machinery. 

YKK Aquaguard Zips: Enhancing water resistance where it matters

No matter how well sealed the rest of a product is, the bag entrance represents the biggest hole that water could enter. That’s why we only use the best premium zippers. YKK Aquaguard zips are the benchmark when it comes to durability and reliability and give you an added level of reassurance that the contents of your bags will stay dry.

Hypalon Zip Garages

A zip garage is what it sounds like; a little shelter where the zipper and pull hides once everything is fully zipped up. This has two functions; first of all it provides some additional protection from any gap left by not completely closing a zip by a millimetre or two and it helps keep dust and dirt off the zipper. We use Hypalon for this, which is a lightweight, fully rubberised fabric that won’t get snagged or caught as you access snacks on the go. 



So, we know that on paper our bags should be more than waterproof enough for your next adventure, but “on paper” means very little when you are heading out into the wilderness for a few days. As well as putting all of our gear to endless testing in the field, we also run in-house tests and commission certified scientific checks on our fabrics and construction. 

In-house testing: Hydrostatic head tests

We want to make sure our fabrics meet our expectations of waterproof performance. To do this, we conduct something called hydrostatic head tests. In short, we clamp some fabric over a hose and measure at what pressure water begins to seep through. It’s exactly the same kind of test that jacket fabrics and tents are subjected to. We only use fabric that far exceeds what we would ever expect to see in real life use.

Ingress Protection (IP) Certification: Ensuring the end product withstands water and dust ingress

Once again, the fabric is only part of the puzzle; we care about the end product. We get our bikepacking gear independently IP certified. This rates its ability to withstand varying levels of moisture and dust ingress. That includes zips, seams and the overall production. This gives us – and you – the assurance that our products offer reliable protection against the elements, no matter the conditions.


IP ratings can appear quite complicated, but once you know how to translate them, the letters and numbers begin to make sense. Not all of our products are tested for Ingress Protection, but where they are, its IP rating will be listed on the product page.


Dust can be just as pervasive as water, so IP ratings measure for dust as well as water. There are no specific IP tests for bags, but the IPK rating is closest to the real world environment for a bag. Products are subjected to being showered in dust for a prolonged period and the rating means “totally protected from dust ingress”.


A similar process is applied for water testing. A hose is turned on our products for a set duration in different directions.


At Restrap, we believe that the performance of our products on day one is only part of the story. We want you to be able to enjoy that same performance day after day, come rain or shine. That can mean a tough life and sometimes even the strongest products start to show their age. That’s why we offer a lifetime warranty: so should the worst come to the worst, we will work to make sure your gear is given a new lease of life. The benefit of manufacturing all of our products in house is that we can always seek to take the sustainable approach and repair before we replace.


We will give you the best possible starting point to keep your gear dry, but there are always a few extra steps that you can take to protect your most important gear. 

A dry bag is a closed bag

It might be stating the obvious, but our bags are only waterproof when they are closed. Each time you open a zip or unroll a dry bag represents a chance for water to begin creeping in. That’s also why we measure the volume of our drybags with three full rolls of closure. Any less than that risks water ingress. 

Separate out kit

Linked to the above point; if you put something wet in a waterproof bag, that moisture will be trapped inside. We always try to use a separate bag for kit that is wet (or is likely to get wet) like bivvy bags or tents. We have a lot of packing tips in our how-to guides. 

Keep valuables doubly protected

Accidents happen and sometimes bags can pick up unseen wear holes or punctures. We recommend that you keep electrics in a separate plastic bag; especially if you are carrying them in a frame bag. We also recommend putting dry clothes and sleeping bags in a separate dry bag within your bar or saddle bag, as this protects against mistakes like throwing a wet waterproof jacket in with your only pair of clean pants…


In short, we worry about our gear, so you don’t have to. From advanced coatings to meticulous construction techniques, every aspect of our products is engineered to deliver uncompromising protection in the most challenging outdoor environments. Explore our range of waterproof bikepacking gear today and head out into the elements with confidence.

We want you to be confident in our commitment to quality and reliability. Our materials and design features are chosen for their durability, resistance to the environment, and ability to withstand wear and tear, ensuring that our products are built to last and perform at their best in any situation. This is why all our products are sold with a Lifetime Warranty.