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When hiking, it is essential to layer your clothing, as this will help to regulate your temperature and ensure you stay dry and comfortable. Your base layer is one of the most important to get right, and this guide serves as a way of helping you make the best choice when it comes to base layers.
What is a Base Layer?
A base layer is a layer of clothing that is worn underneath all of the others. It is designed to be worn close to the skin, so it should fit snugly but not so that it is tight. In short, make sure you buy the correct size.
Your base layer is worn this way so that it traps air and provides you with the best level of insulation. Since the material is designed to wick away sweat, it will keep you dry which enables you to better regulate your body temperature.
How Do Base Layers Work?
Base layers are designed to keep you comfortable while hiking by controlling your body temperature, providing insulation, and keeping you dry. There are three main ways in which base layers work.
When you get wet, your body will begin losing heat much more quickly. This is because water has a thermal conductivity 25 times higher than that of air. If you wear wet clothing, this can result in friction and chafing, which can be uncomfortable. Because of this, hikers wear a base layer to prevent moisture and the resulting problems. The material wicks away sweat and exterior moisture like light rainfall allowing it to evaporate without making contact with the body.
When the weather is a little warmer, you may not need as many layers. Many people opt to wear only a base layer and this can protect the skin from things like UV rays, brushing against plants and foliage, as well as offering protection from a backpack, which may otherwise chafe.
One of the main benefits of your base layer is that it can help to keep body heat in and prevent you from losing it as quickly. This is especially important in colder weather. In warmer weather, once you start sweating, this can also mess up your body temperature, but a base layer will wick moisture and help to regulate this.
That said, it is worth keeping in mind that it’s very rare to find a base layer that will work equally well in both hot and cold weather. You would normally need a separate summer and winter base layer.
Types of Base Layers
As you may assume from the name, the base layer sits at the base of several other layers. You don’t always have to wear all layers; it very much depends on the weather. But as a rule, there are three that you’ll want to have at the ready.
Your base layer is often considered one of the most important as it helps to regulate your body temperature and keep you dry. Without it, the other layers wouldn’t function as well, and you would find yourself very uncomfortable.
This layer is usually made from a moisture-wicking material and can be made up of several things. This might include briefs, boxers, sports bras, t-shirts, and long-sleeved tops. While there are several different types of material for base layers, you should avoid cotton as this will simply absorb moisture and not wick it away.
The mid-layer is worn over the base layer and under the outer layer. Its primary purpose is for insulation and to keep you warm. For this reason, it is sometimes called the insulation layer.
Mid-layers come in many options, including trousers, tops, and insulated jackets. Furthermore, lots of different materials are used, such as down and fleece. These will not only keep you warm but continue to insulate you even if they get wet.
The final layer is the outer layer which is designed to protect you from things like rain, snow, wind, and other elements. However, they’re also designed to let heat and moisture escape, so you don’t get too hot.
There are different kinds of outer layers. The hard shell is the most protective and is intended for use in extreme conditions. It is fully waterproof and has other features like taped seams and adjustable cuffs to keep out cold and moisture.
Soft shell outer layers are designed for use in less extreme conditions and are generally more comfortable owing to how flexible they are. However, they aren’t usually fully waterproof but are a great choice for cool weather. Moreover, they tend to be more breathable.
You might choose an insulated down jacket as an outer layer if the weather is very cold. However, it’s important to note that these are not waterproof, so you will need a lightweight waterproof to go over the top if it will rain or snow.
How Tight Should Base Layers Be?
A base layer is intended to fit close to the skin, but it shouldn’t be overly tight so that it feels restricting or uncomfortable. As a general rule, you will want your base layer to be tighter than a regular t-shirt. Base layers are designed for a slim fit, so you won’t need to size down; just get your regular size.
The only time that a base layer should be a little looser is if it is a little warmer or you are wearing a heavy base layer. This allows you to put other things underneath. But generally speaking, if it is loose, it won’t be as effective.
Synthetic vs. Natural Fabrics – What is Better?
Base layers come in a range of materials, both man-made and natural. When choosing a base layer, it’s worth considering your options as there are pros and cons to each type.
Merino wool is largely considered to be one of the best natural materials for base layers. This is because it is naturally warm and breathable but isn’t uncomfortable like other types of wool. In fact, you will find it to be breathable and light as well as offering a good fit. It also has antibacterial properties, so it will prevent odors.
However, owing to how well merino wool performs, you will typically find that these products are a lot pricier.
There are lots of synthetic materials used to make base layers, including spandex, rayon, nylon, polyester, and elastane mixes. One of the major benefits of many of these, particularly polyester, is that it will dry very quickly. Moreover, it’s beautifully lightweight and incredibly durable.
That said, they aren’t quite as good as something like merino wool but come pretty close for a man-made material. In fact, in some cases, you can buy merino wool blends with things like polyester for the best of both worlds.
Cotton does have a lot of benefits but not where base layers are concerned. The main problem is that it will absorb sweat which keeps you wet. In very cold weather, this can quickly lead to hypothermia.
Silk is a natural fabric that has many of the same properties as merino wool. However, since the fibers are much finer and can be more finely woven, many agree that it is more comfortable on the skin. It is also easy to care for, and garments will not need ironing.
That said, silk is not quite as effective as merino wool when it comes to being thermally efficient.
Some base layers are made from a blend of man-made and natural fabrics. These are ideal if you want to get the best properties of both types of material. These wool-blend fabrics are very warm, but they won’t be as insulating as a 100% merino wool garment.
The addition of man-made fabrics like polyester will make the item feel more comfortable on the skin. However, do be mindful that there are some products blended with cotton, which is something you will want to avoid.
How to Layer During the Winter
It is essential to properly layer your clothing during the winter to prevent you from becoming cold. A good base layer is the best place to start and should consist of bottoms and a shirt. You should stick with lightweight materials to reduce the risk of getting too hot while you’re hiking but make sure it has a tight fit.
Next, you will choose your mid-layer, which is typically made from fleece. Much like your base layer, this should be lightweight, but it doesn’t need to be tight fitting. However, many people agree that puffier clothing will provide the best insulation.
You may then wish to wear a further insulating layer for very cold weather. The material can be synthetic, or you may choose something natural like down. Both are good as long as the garment fits comfortably between your other layers. If the weather is going to be wet, we would suggest going for a synthetic material as this retains its function much better even when it is wet.
For winter hiking, the last layer should be a waterproof outer shell. This protects you from the weather but is also important if you are going to be doing winter activities in the snow like skiing or snowshoeing. Look for jackets that feature Gore-Tex for the best waterproofing and breathability.
How to Layer During the Summer
Just because the weather is warm, that doesn’t mean that you still can’t benefit from layers. In fact, if you want to stay comfortable, they’re a must. How you layer your clothes will very much depend on the type of hiking you are doing.
If you are only completing a half-day hike, then a two-layer system should be more than enough. This consists of a base layer and a waterproof outer layer. You can choose a short sleeve base layer during summer if you prefer, and your outer layer should be lightweight enough to carry should you not need to wear it. However, it should be waterproof and wind-resistant as the weather can sometimes change in summer depending on various factors like your location.
If you’ll be heading out for a full-day hike, then we would suggest using a three-layer system. As well as the base and outer layers discussed above, it’s a good idea to fleece mid-layer that provides insulation should things get a little chilly.
Finally, for multi-day hikes in summer, you would probably want to go for much the same as you would on a full-day hike. However, with the risk of changing weather, it might be worth including an insulated jacket instead of a fleece mid-layer as this is more lightweight and better suited to a wider variety of conditions.
Important Factors to Consider When Choosing Base Layers
Choosing the right base layers is essential for maximum comfort and effectiveness in keeping you protected from moisture and cold temperatures. Make sure to assess all of the following features before making a decision on the right base layer for your adventure.
As we have discussed, different fabrics have different benefits and drawbacks. When choosing a base layer, you should consider what the conditions will be like and compare this to the fabric options at your disposal.
Man-made fabrics are typically more durable and provide you with a better fit. However, natural fabrics such as merino wool cannot be beaten when it comes to insulation. As mentioned earlier on, anything containing cotton should be avoided.
Your base layer needs to be tight-fitting in order to perform at its best. That doesn’t mean choosing something so tight that it is uncomfortable. Most products will be designed for a slim fit so you will only need to choose your regular size. Also, make sure that the garment doesn’t ride up and expose any skin when you move around as this can be uncomfortable.
Because different base layers are designed for use in different conditions, they come in a range of different weights.
For starters, there are lightweight base layers that are intended for use in all kinds of weather conditions, both hot and cold. They’re very popular owing to how versatile they are and how well they wick away moisture.
You might choose a mid-weight base layer which is just as versatile as it can be worn alone or over a lightweight base for added insulation. Worn alone, they’re popular for summer sports, particularly with a lightweight outer shell.
There are also heavy-weight base layers, but these are normally used only for hiking in winter. They are very insulating and dry extremely quickly. Some people will wear them alone during spring, but you may find that you get too warm.
The last thing that anyone wants is to have base layers that are uncomfortable, especially when you are going on a longer hike. Ensuring a good fit is the best place to start but also think about how the material feels on the skin. Some people find certain materials itchy or irritating so it’s best to try them out before committing. It’s worth noting that merino wool shouldn’t be put at the back of the line for fear of itching. Unlike other types of wool, it’s very soft and comfortable on the skin.
Choosing a base layer with good breathability is essential if you want to stay dry and comfortable. As we have discussed, things like cotton will hold onto moisture and as soon as you stop, will make you feel very cold.
A good base will wick away moisture and let it evaporate, keeping you dry and your body temperature balanced. Synthetic fabrics like polyester are exceptionally breathable, as are natural fabrics like merino wool and silk.
How to Wash Base Layers Correctly
Once you have found the perfect base layer, you are going to want to get as much use out of it as possible. This means taking good care of it, and that starts with washing it correctly.
The great thing about synthetic base layers is that they are so easy to care for, and they can be cleaned in the washing machine on a regular cycle.
However, if they are particularly dirty, you may wish to soak them first in a solution of warm water and ¼ of a cup of scented vinegar. Soak the garment for 30 minutes before running it through your normal cycle.
While some garments can be dried in the tumble dryer, this should be done on a low setting. Air drying is better, where possible, and you should always consult the care labels on the garment for any special requirements.
As with synthetic materials, you should always check the care label on your merino wool garments for the best instructions for washing. But generally speaking, you will want to wash on a cycle lower than 40º and make sure that you turn the garment inside out. It is also recommended to wash your merino wool base layer within the first three wears. While it may not yet need it, doing this will stop it from piling.
While your washing machine may have a wool cycle, there is no need to use this for merino wool. Also, make sure that you do not add fabric conditioner to the machine.
Once you have washed your garment, you will need to allow it to air dry. Try to avoid wringing it out but place it on a flat surface to dry, out of the way of direct sunlight.