Shell Layer Fabric Guide

Sewing Tutorial

The "shell-layer" is the fancy word for the outerlayer of your
outdoor clothing - these are your jackets, pants, coats, capes, gaiters, and more.

Shell-layer fabrics can be distinguished as either "Hardshell" or "Softshell". This only refers to how flexible the fabric is. On top of this, they can have multiple properties, such as being water- or windproof, water- or wind-resistant, breathable or partly breathable, or they can have additional padding for warmth. Below is a basic guide to Shell-layer fabrics to help you find the perfect fabric for your adventure.

Hardshell or Softshell

"Hardshell" and "Softshell" only refers to the flexibility of the fabric. Hardshell fabrics are rigid and firm. These fabrics can come with a coating on the inner side of the fabric. This coating can be uncomfortable if left bare, so our patterns include a lining to cover it. Softshell fabrics are stretchy. These fabrics can come with a lamination instead of a coating, which is less rigid.

Hardshell and Softshell fabrics can be:
1. water- and/or wind-proof or
2. water- and/or wind-resistant and/or
3. breathable

Water- & Wind-proof fabrics

Often when a fabric is waterproof, it's also windproof. These fabrics are essentially sealed, which means they don't allow any water or air to enter at all. Often these fabrics are made of rubber, polyurethane or silicone.

There are waterproof fabrics to fit every use case. The fabrics differ in their barriers and weights. The fabrics can have barriers such as coatings (rigid), laminations (flexible), or wax (rigid). Heavy-weight fabrics are used for outside furniture and to cover equipment, mid-weight fabrics are best for backpacks, tents, bags, gear and garment reinforcements, while light-weight fabrics are best for clothing, ultra-light gear and light-weight reinforcements.

While all material lets some sweat out, water-and wind-proof fabric let out the least. If you expect to sweat a lot on your adventure, and your base-and mid-layer garments aren't very moisture absorbent, you might end up wet. Adding in ventilation holes, such as armpit holes in form of grommit holes or zippers, is always possible. But it might also be enough to wear a water-and wind-resistance fabric.

Water-& Wind-Resistant Fabrics

Water-and wind-resistant fabrics have a temporary layer that is applied to the outer fabric side. You can see this labelled as 'DWR impregnation' meaning 'Durable Water Repellent'. It's important to notice that DWR is only temporary and tends to come off after normal wear and tear. Re-applying the impregnation with a wash-in liquid, spray or re-waxing is easy though. The difference between water-and wind-resistant fabrics is that wind-resistant fabrics have a different type of weave.
While you'll get wet in very heavy rain and you'll feel a breeze in heavy winds, water-and wind-resistant fabrics will keep you dry and warm in moderate rain and wind conditions while also being breathable.

Breathable fabrics

There are many kind of breathable fabrics on the market. They come as stretch, non-stretch, with minimal to high levels of breathability, and many other type of features. The level of breathability in a final garment all depends on the composition, the membrane used (lamitation or coating), the design, features and finishing of the seams.

When you think about staying dry, most people only think about the conditions that come towards them, for example rain, snow and wind. However when you move, you're also creating moisture in the form of sweat. The body sweat needs to be transported quickly from your skin through your layers and crucially, through your final shell layer.
If your body moisture cannot exit your shell layer, you will get wet from the inside. Therefore, to stay as dry as possible, you'll need a breathable water-and/or wind-resistant fabric. DWR is only a cover on the fabric which allows it to repel water drops from entering while allowing sweat droplets, which are smaller, to exit.

Breathable fabrics differ so much so it's best to inform yourself and
compare details in a store.

Waterproof & Breathable?

Waterproof fabrics shouldn't let any water come through from the inside or outside. The seams are sealed and placed at strategically good places. Any breathablity is achieved through ventilation openings, such as grommit holes or zipper openings. But as you start sweating during your trip, your body vapour cannot pass quickly enough through these openings. As you try to protect yourself from rain, you might actually end up getting more wet underneath your garment.
So a waterproof and breathable fabric is an oxymoron. Perhaps a better choice is to use a water-resistant shell with DWR (Durable water repellant) impregnation that can breathe and when conditions demand, putting on a separate thin layer of waterproof rain gear.

Layered Fabrics

Nowadays you'll also often see layered fabrics. It essentially means that different fabrics are glued together. This allows you to have a different fabric on the inside and outside of your garment, for example with a single fabric you can have abrasion-resistance on the outside while softness against your skin on the inside. Nearly any fabric (water-proof, water-resistant, breathable,..) can be layered.
Layered fabrics come in 2, 2.5 to 3 different layers. When buying these fabrics, you'll notice different words used to describe how the layers are glued together, for example "lamination" or "bonding". These basically mean the same thing.

Layered fabrics are great for outdoor clothing because they allow you to make use of the different fabric properties while still being lightweight and easier to work with since it's only one fabric.

Coated Fabrics

Coated fabrics are 2-layered and used to make the fabric waterproof. This coating is on the inner side of the fabric, and can easily be seen. The coating is commonly made from PCV (polyvinyl chloride) ,PU (polyurethane), Arcylic or Silicone. If you intend to use a coated fabric for a full piece of clothing, you'll need to make a lining. Keep in mind, that this garment won't be breathable at all. Coated fabrics, however, are excellent in outdoor clothing to use as reinforcements for instance around the butt or knees. They are also great to use for gear such as covers, bags and tents.

Seam Tape

If you need a water-proof garment or gear, you'll need to keep in mind that water can still enter through the seams. To avoid this and make it water-tight, you can seal the seams with seam tape. These tapes are easy to apply. They have glue on one side and can be ironed on. There are two different types of seam tape on the market: 2-layer and 3-layer. It's important to use a 2-layer or 'Action Seam Tape' for 2-layered fabrics. And a 3-layer seam tape for 2.5- and 3-layered fabrics. The 2-layer seam tape will come off easily if attached to a 2.5- or 3-layer fabric.

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