Layering clothes: a guide

In our regular monthly blog series, writer and hiker Phil Thomas shares the trade secrets of his passion: the Great Outdoors. He lives in North Wales and spends most of his spare time writing or walking in the hills with his girlfriend and their crazy Patterdale terriers.

Phil shares his knowledge of the practical side of walking with real life tips than can help you enjoy the mountains more and maybe even save you if you get in a spot of bother. This month, as the weather takes on a distinctly autumnal feel, we discuss layering clothing, really important for a comfortable and safe day on the hill… 

Walk into any outdoor clothes shop – or browse online – and you’ll come across clothing items described as being ideal for ‘layering’. But what does that mean exactly? Is it just marketing-speak to tempt you into buying stuff you don’t need, or is “layering” as important as the manufacturers make out?

So what is a clothing ‘layer system’?

It’s simple, really, as most of us wear layers every day. Up in the hills, wearing layers of clothing takes on added significance. You can add them or remove them depending not just on the weather, but also how hard you’re working.

Think of a typical hill walk. You set off comfortable enough. Then as you start uphill and exert effort, you get hot. It’s time to take off a layer or two. Stop for something to eat and you soon cool down – so get those layers back on. Similarly, it’s almost always colder and windier at the summit than where you start from. You’ll be glad of that extra layer once you reach the top. Even on the best summer days, don’t underestimate the fickle mountain weather.

A very basic layering system consists of three layers. Each layer has a specific role to play, so when you’re buying your clothes it’s a good idea to think about what you want that item of clothing to do most. Does it need to be waterproof, or is warmth the priority? Let’s take a look at each layer.

Against your skin – the base layer

Base layer clothing tends to be lightweight but must be comfortable. Some cheaper base layer clothes have seams which can rub. Base layer clothes come in all shapes and sizes, from trousers (or tights) to long- and short-sleeved (T-shirt) tops.

The primary purpose of base layers is twofold: first, it’s an extra layer of warmth. This is the layer you can skip in the warmer summer months. Its second purpose is more specialised: wicking moisture away from you.

What does this mean? Wicking is a process that takes sweat away from your body. You might wonder why you would need clothing that could do that. Well, think about the last time you worked up a sweat climbing a hill or mountain.

What happens when you stop or reach the summit? The sweat – a healthy, perfectly naturally process when you’re exercising – now works against you by cooling on your skin and making you cold.

Clothing with wicking properties will stop this from happening. Don’t dismiss “wicking” as marketing hype – it really does make a difference. Merino wool is a great material for base layers – it’s warm, comfortable and wicks sweat away from you. You’ll pay a bit more but it’s worth it.

A good fleece – the mid layer

The mid (or middle) layer has one principal job – to keep you warm. Mid-layers will go over the top of your base layer and (usually) sit underneath a waterproof outer layer.

The mid-layer probably has the easiest role and so here you’re looking for something effective but easy to carry. You need a fleece that will keep you warm but is also lightweight to carry, should you decide to take it off and stuff it in your pack while you’re making your ascent.

Fleeces are often classed by weight, from “ultralight” to “heavyweight.” Lighter fleeces tend to be more breathable while some warm fleeces are also bulky.

If you walk in all seasons it makes sense to own a lightweight fleece for summer and something more substantial for winter. Just remember that the winter fleece will take up more space in your pack.

The outer layer – is often two layers!

The outer layer is – surprise surprise! – a jacket. But this is where your clothes get smarter still. The simplest outer layer is an insulated, windproof and waterproof jacket – like a sky jacket.

The problem with this for walkers or mountain bikers is that waterproof/windproof jackets are not breathable, which means that sweat your base layer is wicking away from you will stay inside your clothes, making you wet. It’s no fun being in wet clothes.

So the better solution is to wear two separate layers – an insulating layer and a waterproof (often called a “hard shell”). There are also “soft shells” which are more flexible but not waterproof – they may be described as “water resistant”.

The insulated layer is the outer layer that keeps you warm. It’s often made of natural or synthetic down materials and it’s effectiveness is described as fill power. The higher the power number, the more insulating the jacket will be.

The outer shell needs to be big enough to throw over the top of your jacket, so it’s always a good idea to be generous when choosing a size! A hard shell will be waterproof. Ideally you’ll only pull this on in wet weather and take it off when it’s dry, because you will sacrifice breathability. The soft shell is a good summer option – it won’t protect you in a deluge but should keep you dry in light rain, and it will be more breathable.

The choice is yours

Of course, you can wear as many layers as you want while out in the mountains. But the experts tend to agree that the system described above is the best way to wear clothes that suit the activity. You will stay dry, warm and comfortable – but most importantly you’ll be able to add or shed layers as the conditions and your situation dictates.

There are some great outdoor clothing shops in Snowdonia, with perhaps the best choice in Llanberis and Betws-y-Coed. You can shop online for sure, but nothing beats trying clothes on – and maybe it’s even more important to touch and wear clothes designed for the great outdoors. Best of all, if you buy here you’re just minutes away from trying it out for real!