We all know the importance of waterproof and breathable rainwear for our outdoor adventures, but have you ever wondered how it actually works?
Obviously, the main reason we need rainwear is to stay dry, but it needs to ensure that sweat can escape while keeping the rain out or we’ll still end up a soggy mess.
That’s where waterproof and breathable rainwear comes to the rescue, allowing us to stay dry and comfortable no matter what Mother Nature throws our way. But how exactly do these high-tech fabrics manage to keep out the rain while still letting our skin breathe?
In this article, we’ll delve into the fascinating world of waterproof and breathable materials, exploring how they work, the science behind their construction, and the various factors influencing their performance.
Key Takeaways
- Waterproof and breathable rainwear is important for outdoor activities to stay dry and comfortable.
- PTFE is a popular micro-porous material for water vapor but not water droplets, and is used in Gore-Tex and other brands.
- Durable Water Repellent (DWR) coatings improve breathability by causing raindrops to bead up and roll off.
- The 3-layer system (baselayer, midlayer, and shell layer) is essential for proper breathability, and backpacks can be a barrier for rainwear performance.
History of waterproof clothing
Before we dive into the history of waterproof clothing, let’s take a moment to appreciate how far we’ve come. Older rainwear used to be heavy, stiff, and uncomfortable, leaving us clammy and damp on the inside.
Fortunately, the discovery of micro-porous materials revolutionized the industry, followed by hydrophobic coatings to repel water, providing us with lightweight, breathable, and effective solutions to stay dry and comfy outdoors.
The main reasons why we need it
You might wonder why waterproof and breathable gear is essential for your outdoor adventures, right? Well, it’s all about staying dry and comfortable while enjoying the great outdoors.
Waterproof materials, like those found in a layer laminate construction, provide excellent weather protection by keeping rain and snow out, while still allowing water vapor (i.e., sweat) to escape. This is crucial because our bodies generate heat and moisture during physical activity, and if that moisture can’t escape, it can lead to a clammy, uncomfortable feeling.
A good waterproof jacket, for example, will have a high level of water resistance combined with breathability performance, ensuring that you stay dry from both external elements and your own perspiration.
In addition to waterproof and breathable layers, most rainwear also features a durable water-repellent (DWR) finish. This treatment causes raindrops to bead up and roll off the surface of the fabric, preventing them from soaking in and compromising the breathability performance.
The combination of waterproof materials, breathability, and DWR treatment provides a level of weather protection that is unmatched by non-waterproof gear. Furthermore, the durability of these materials ensures that you can rely on your rainwear for many outdoor adventures to come.
So, whether you’re hiking, biking, or just out for a walk in the rain, investing in waterproof and breathable gear will give you the freedom to truly enjoy your time outdoors, no matter the weather conditions.
The Problem With Old Rainwear
Originally natural products like furs and skins of animals were used to keep the rain off. These were heavy and not entirely waterproof. However, with the advent of plastics and other materials, materials like PVC came to the fore.
While far more waterproof than skins and furs, PVC clothing often feels like you’re trapped in a stuffy, damp cocoon, unable to breathe, and soaked in your own sweat if you attempted anything strenuous.
This discomfort stemmed from the fact that traditional rainwear prioritized waterproofing over breathability, often using a double PVC layer construction that did a great job of keeping water out but left you feeling hot and clammy inside. In fact, studies have shown that a person’s sweat rate can increase by up to 30% when wearing non-breathable rainwear.
The lack of classic breathability, combined with the potential for body oils and dirt to clog up the waterproof membranes, made old rainwear a less-than-ideal option for outdoor enthusiasts seeking protection from the elements without sacrificing comfort.
Thankfully, the innovation of backcountry rainwear has come a long way since those days, with advances in microporous membrane and hydrophilic coating technologies that have revolutionized the basics of rainwear technology. The development of layer construction systems, such as 2-layer, 2.5-layer, and 3-layer systems, has allowed for more efficient water vapor transmission while maintaining waterproof capabilities.
The Discovery of Micro-Porous Materials
In the 1950s, Bill Gore left his job at DuPont to focus on exploring the potential of the polymer polytetrafluoroethylene (PTFE). However, it was his son, Bob Gore, who made a groundbreaking discovery in 1969.
By chance, while trying to make the membrane thinner, he found that PTFE could be stretched or “expanded,” creating tiny holes. These holes were big enough to let water vapor through, but not big enough to allow water droplets through. This discovery led to the birth of Gore-Tex.
Despite this breakthrough, it took another seven years for the microporous, water-repellent, and vapor-permeable material to be utilized in clothing fabrics. But, in 1976, the first Gore-Tex rain jacket was introduced to the market.
The discovery of micro-porous materials revolutionized the world of outdoor gear. These microporous membranes transformed gear from stuffy, damp cocoons to comfortable, breathable havens for adventurers.
Types of waterproof materials used in the construction of outdoor gear
In our exploration of waterproof and breathable materials, we’ll dive into the two main types, micro-porous membranes and hydrophobic coatings (DWR), and how they are used in conjunction to create the modern garments we wear out on the trails.
This all really started with Gore and the discovery of micro-porous materials like PTFE.
Microporous Membranes
So, what exactly is the microporous membrane? It’s a thin layer of material that is waterproof and breathable, allowing air and moisture to pass through while keeping us dry. These materials work by having microscopic pores that allow water vapor (sweat) to escape while keeping out larger water droplets (rain).
There are several types of membranes available, each with its own unique properties and benefits. Some are made from synthetic materials like Gore-Tex, while others use natural materials like eVent.
One of the most well-known and widely used waterproof and breathable rainwear materials is Gore-Tex. This remarkable material has set the standard for performance in layer rain jackets. It offers a combination of dedicated material layers that provide fair breathability, fair wind resistance, and a high level of protection from the elements.
At the core of Gore-Tex is a performance layer, made from expanded PTFE, which consists of billions of micro-pores that allow water vapor to pass through while keeping water droplets out. This layer is then bonded to other materials like polyester strands, creating a durable and effective barrier against wind and rain.
The result is a versatile and reliable choice for outdoor enthusiasts who need top-notch waterproof and breathable rainwear to keep them dry and comfortable in a wide range of conditions.
However, if the garment becomes waterlogged, called ‘wetting out,’ it reduces the garment’s breathability and lets water through, making it basically useless.
Luckily there have been developments in hydrophobic material and coatings.
What Do Hydrophobic & Hydrophilic Mean?
A hydrophile, or hydrophilic molecule, is one that adores water – it’s a true ‘water-lover’. On the flip side, a molecule that shuns water, repelling it, is labeled ‘hydrophobic’.
These labels, hydrophilic and hydrophobic, categorize molecules or substances based on their relationship with water.