What’s the ideal weight for mid-layer insulation in winter?

Insulation Weight and Loft

When it comes to layering for winter activities, the mid-layer plays a crucial role in retaining body heat. A good starting point for the ideal weight of a mid-layer insulation is 300-400 grams, which is roughly equivalent to a mid-layer with a loft of 5-7 inches. This weight and loft range can be achieved with a mid-layer of synthetic insulation, such as Polarguard or Holofill, or natural insulation like down.

Mid-Layer Thickness and Activity Level

The thickness of the mid-layer can vary depending on the activity level and the ambient temperature. For low-intensity activities like cross-country skiing or snowshoeing, a thinner mid-layer with a loft of 3-5 inches may be sufficient. However, for high-intensity activities like backcountry skiing or ice climbing, a thicker mid-layer with a loft of 7-9 inches may be needed to retain body heat.

Additional Considerations

In addition to weight and loft, the mid-layer should also be considered in terms of its ability to retain warmth when wet. Synthetic insulation is generally a better choice than down in wet conditions, as it maintains its insulating properties even when damp. Natural insulation, on the other hand, loses its insulating properties when wet and should be avoided in wet conditions.