Clothing Layers and Why They Are Important

Most active outdoorsy adults will agree that dressing in multiple layers is the best protection against the elements. Generally we reference at least three different layers. Often overlooked, the inner layer provides comfort by pulling moisture away and sequestering it away from the skin. This is what we refer to as the first or base layer. The mid layer provides warmth, often referred to as the insulating layer.

The final outer layer protects one from wind, water, and other elements. Also referred to as a shell layer, the outer layer works as protection over the other two layers.

Often high performance garments combine two adjacent layers, as in the case of ‘polar’ weight undergarments that aim to provide both comfort and insulation. Here at Tuff Kids Outdoors, we tend to shy away from apparel labeled for “performance”. It’s partially because this is a marketing gimmick, but more importantly, we do not believe this is the best way to prepare for all day outdoor comfort.
We believe that any parent on any budget, armed with the right information, can dress kids for success outdoors.

BASE LAYER
The first rule is to avoid cotton at all costs as a base layer. When the body heats up and sweat is produced, cotton absorbs and holds the moisture. There is limited wicking action with cotton, so moisture sits next to the skin, depleting warmth from the body when it’s cold out, and limiting the body’s own ability to cool when it’s hot out.

The best inner base layers draw the sweat away from the skin to the next layer, which allows the youth to maintain a constant core body temperature and stay comfortable. The transfer of moisture happens due to capillary action, therefore material composition determines whether a garment will absorb or simply help disperse moisture. Merino wool is by far our favorite base layer. Merino is composed of natural somewhat absorbent small fibers. For this reason, Merino is soft and comfortable and it excels at quickly pulling moisture away from the skin, while maintaining insulation. Fully synthetic materials cannot absorb large water molecules, although with small fiber sizes and more surface area, when they get wet, moisture is able to quickly evaporate. While Merino wool is highly odor resistant, we can’t say the same for fully synthetic materials which can absorb foul-smelling body oils.

MID LAYER
We can be a little more lax on what we choose for a mid layer, especially when on a budget. While cotton garments usually work for this layer, because they absorb moisture easily they can completely lose their ability to insulate when wet. If you’re planning an active outdoor adventure where the temperature can drop precipitously, you really need to make sure you have the ability to stay dry.

The mid layer is key in colder weather to provide essential insulation. The use of multiple thin layers facilitates adjustment of warmth. Appropriate fitting garments are required to achieve maximum moisture transfer by capillary action from one piece of clothing to another. Wool has often been the traditional mid layer material for adults. It has good insulation even when wet, absorbs moisture but does not feel wet even when it holds significant moisture, and transfers moisture.

For kids though, our favorite mid layer for outings is fleece. Fleece made from PETE or other synthetics has many of the features of wool, but is lighter. It provides good insulation even when wet, absorbs very little moisture, and dries quickly.

For puffy vests and jackets, down has a very good warmth:weight ratio, and can be packed down (squeezed) to take very little room. On the downside, it is expensive, makes a thick garment, dries slowly, loses its insulating properties when wet or compressed, and stops lofting properly after being washed several times. Synthetic fiber fills such as polyester is used similarly to down, and is much more common on the market for kid’s gear. Synthetic fill does not have the same warmth:weight ratio, though it is affordable, provides better insulation when wet, dries quickly, and absorbs very little moisture.

OUTER LAYER
The outermost clothes should block wind and water, and have good mechanical strength to avoid rips and tears. Ideally the outer layer lets moisture through to the outside (breathable), while not letting wind and water pass through from the outside to the inside. There are a ton of waterproof and breathable outer layers on the market these days, although even the best and most expensive materials involve a slight trade-off between breathability and water- and wind resistance.

If you find a jacket or pant that feels like rubber or plastic, it probably is. While these garments offer excellent protection from water and wind, they do not let moisture through. Often to compensate, such jackets have flap-covered holes and are very loose-fitting. Often these garments leave the body feeling wet and clammy.

Waterproof breathable outerwear garments all start with either a nylon or polyester shell. Inside, they all have a laminated porous membrane that blocks liquid water, but lets through some level of water vapor / sweat. Often these materials have a Durable Water Resistant (DWR) finish/coating as well. At one time you could rely on the most expensive materials being the most waterproof and the most breathable. This is no longer the case.

Gore-Tex and eVent are well known high-performance fabrics in this arena. Each rely on a proprietary porous membrane. Common to most other waterproof / breathable garments is a simple Poly Urethane (PU) porous membrane. The quality of each fabric sadly is not determined by cost, but instead by several factors including yarn and weave type, whether a DWR finish was applied, as well as how the porous membrane was constructed and/or applied. Most outer shell fabrics are rigorously tested, and waterproofness and breathability are measured. Often you just need to do some comparison shopping!

Stay tuned for more information from Tuff Kids Outdoors on quality waterproof breathable fabrics.