After understanding the principles of cold-weather apparel, the next step is to decide on a layering strategy.
For maximum versatility, each garment should have one unique function within the clothing ensemble. This allows the clothes to be effective for a much wider range of conditions – and specialized garments usually perform better too.
Although each situation is different, clothes almost always need to fulfil a combination of the following roles:
- Manage perspiration. Water is constantly lost through the skin, even when sedentary, which carries away heat. The further the moisture is transported from the skin before evaporating, the less heat is lost.
- Trap air for insulation to maintain a stable core temperature while active.
- Increase insulation when sedentary and generating less body heat.
- Block wind to preserve the insulating still air layers inside and between the clothes.
- Protect from precipitation to prevent the ingress of water and loss of insulating air.
As there are common functions that clothing systems need to fulfil, so there is a common sequence of layering to meet these requirements. The constituents of the most popular four-layer system are described below.
The first layer worn directly next to the skin should be fast-drying to prevent the accumulation of heat-conducting moisture from sweat.
Thin synthetic fabrics make good base layers since they are durable and dry faster than natural fibres.
Natural fibres – especially cotton – absorb moisture and dry slowly so are dangerous in cold weather.
Skin can stick to cold surfaces. Never handle heat-conducting metal or ice without at least a thin liner glove on. Special care is also needed with liquids like alcohol or gasoline which cause serious cold burns upon contact.
What to buy
- Long sleeve top, long johns or boxer briefs, liner gloves, liner socks
- Synthetic fabrics, usually polyester or sometimes nylon
- No cotton
- As thin as possible to dry fast
- Comfortable feel against the skin
- Flat seams to prevent chafing.
- Optional: anti-odor treatment to reduce laundry frequency in long trips
Over the base layer are worn one or more insulating mid-layers to hold in body heat. The amount of insulation should be tailored for the anticipated level of exertion.
Fleece garments are great for insulation since they are durable, inexpensive, and they don’t trap sweat.
Fleece is less appropriate for the feet since the best-fitting socks are knitted rather than sewn. Wool or polyester work best and can be combined with some nylon for durability. When layering socks, size appropriately: outer layers sometimes need to be of larger sizes than inner layers so that they fit comfortably without too much compression.
Hands are difficult to keep warm. Mittens are warmer than gloves since the fingers can warm each other. Socks can be used to cover the hands if the mittens are lost.
When body’s core is cold then blood flow will be diverted away from the hands and extremities to warm up the vital organs; keep your torso, head and neck well insulated with a warm hat and a scarf or neck gaiter. Attention should be paid to protecting the ears, nose, cheeks and chin which are more susceptible to frostbite.
What to buy
- Fleece hoody, gloves/mitts, beanie; fleece pants if needed.
- Any 100% polyester fleece; no cotton
- 200-weight fleece fabric (the thickness of a sweater) for most uses
- Lighter 100-weight fleece (T-shirt thickness) for high intensity activity
- Optional: Smooth outer face (less pilling, easier to slide on outer layers)
- Optional: Anti-odor treatment, flat seams, YKK zips
- Balaclava if conditions warrant (eg. temperature below -10°C)
- Knitted wool- or polyester-blend socks (anything without cotton is normally ok)
Seal in the insulating air with a wind-proof outer layer. This is usually a thin, tightly woven nylon garment. It may be water-repellent, but shouldn’t be waterproof – clothes which are totally waterproof block the evaporation of sweat and make you wet from inside when you are active. A waterproof layer can be used when sedentary.
The outer layer for feet is correctly fitted boots. When determining the size, make sure to try them on with the socks that you will be wearing.
UV-blocking goggles or wrap-around sunglasses are always necessary for protecting the eyes, and to prevent them from drying out in the wind.
What to buy
- A hooded wind jacket (super light) or breathable soft shell (more abrasion resistant)
- Tightly woven nylon fabric
- Unlined (ie. no fleece lining)
- All openings (cuffs and hems) must have fasteners or elastic
- 5 cm more girth than the layer immediately underneath to create a still air gap of 0.6–1cm between these layers
- Not fully waterproof; water-resistant is ok
- Umbrella, poncho, or hooded rain jacket for use during sustained precipitation
- Nylon trousers, aka ‘hiking pants’ or ‘soft shell pants’
- Correctly fitted pair of boots
- Windproof mitten shells, made of unlined (uninsulated) thin woven nylon
Much less body heat is produced when we are sedentary so more insulation is needed at rest than during activity.
A highly insulated hooded jacket serves this purpose well. It should be worn as the outermost layer when stationary and removed before resuming activity to prevent overheating. Down or synthetic fill provide a high amount of insulation for their weight and allow the garment to be compressed and carried easily in a pack when it’s not in use. The face fabric should be windproof and water-repellent.
Insulating pants are inconvenient to wear and generally not required except in the most extreme conditions.
Cold hands often cause discomfort so consider taking extra mittens or carrying some emergency sources of heat to prevent chilling or frostbite.
What to buy
- Down or synthetic filled hooded jacket with:
- Wind- and water-resistant face fabrics.
- Large enough size to wear as the outermost layer.
- Rechargeable chemical or electric hand warmers.
See actual examples of real clothes (including a list of brand names) so you know what things look like when you go shopping.