Packing for Cold Climates

Cold-weather packing is a volume problem, not a weight problem. The clothes are light and enormous.

Layers, and what each one does

• Base layer sits against the skin and moves moisture away from it. Merino

wool is the usual choice because it manages moisture, resists odour over several days, and keeps some of its warmth when damp.

• Mid layer traps air, which is what actually keeps you warm. Fleece, a

heavier merino, or a light insulated jacket.

• Outer layer blocks wind and rain. It does not need to be warm on its own; it

needs to stop the weather stripping the warmth out of the layers underneath.

The mistake is one very warm coat. Three thin layers are warmer than one thick one and let you take a layer off before you sweat, which is what keeps you dry.

Fabric weight, in gsm

Base layers are sold by fabric weight in grams per square metre. Roughly:

• 150 gsm is a summer or three-season weight, and the one to travel in.
• 190 gsm is the mid-weight that covers most of the year.
• 250 gsm is a genuine cold-weather weight, warm enough to work as a mid layer.

Extremities first

Most heat is lost where you are thin: hands, head, feet. A hat and decent socks weigh almost nothing and make more difference than a heavier coat.

Do not sweat

Sweat is the real enemy in the cold, because damp clothing stops insulating. Start a walk slightly cold, and take a layer off before you need to rather than after.

Packing the volume

Compress the bulky things and leave the rest loose. A compression sack pays for itself on a winter trip and does nothing much in summer. Wear the bulkiest item on travel days rather than packing it.