Bamboo clothing in winter and where the layers belong

Short answer: The layer closest to the skin should move moisture, the middle layer should insulate, and the outer layer should keep the wind out. Swap the order around and none of the layers work as they should, no matter how good each piece is.

Innermost moves moisture

If the inner layer is damp, it cools the skin no matter how much sits on top, because moisture carries heat away from the body far faster than dry air does. That is why the material closest to the skin matters most of all the layers. See bamboo undershirt for men.

The middle layer insulates

Insulation comes from still air trapped between fibres or between the layers themselves. Two thin layers create a small air gap between them that holds onto warmth, while a single thick layer does not give the same effect, even at the same total weight. See sweatshirts.

The outer layer keeps wind out

Without a windproof outer layer, the warm, still air the inner layers have created is constantly blown away, and the whole insulating effect disappears. That is the most overlooked part of winter dressing, since people often focus on thickness instead of whether the outer layer actually stops the wind.

The legs are often forgotten

Most people put three layers on the upper body and only one on the legs, even though legs get cold just as easily. A thin layer under trousers, which takes up little room, often does more for comfort than yet another layer on top. See bamboo long johns.

Feet need room

Cold feet are the most common reason for feeling cold all over during winter. Room in the shoe matters more than sock thickness, since shoes that are too tight squeeze the air out and remove the insulating effect entirely. See all bamboo socks for men.

Hands and head lose heat fast

A large share of the body's surface area sits in the hands and head, and they lose heat quickly if left uncovered. A pair of thin gloves under thicker ones and a hat that covers the ears often make more difference than expected.

Change layers with activity

Moving from standing still to walking briskly raises body temperature, and a layer can usefully come off along the way. Wear layers that are easy to remove and put back on, rather than one large piece meant to stay on the whole time.

Damp clothing cools you extra

Sweat or snow that works its way through the layers makes the cold far worse, because wet fabric carries heat away many times faster than dry fabric does. Change into dry clothing as soon as possible if a layer has gotten wet along the way.

Put the layers together beforehand

Try the combination of inner, middle and outer layer at home before you need it outside in the cold, so you know it fits correctly and does not pinch anywhere once you start moving.