A fleece, an insulated jacket and a gilet all provide warmth, but each suits a different stage of your outing. The right choice depends mainly on how hard you are working, how cold it is and how often you stop.
The short answer: choose a fleece to stay active, an insulated jacket for immediate warmth when you stop or in cold conditions, and a gilet to add core warmth without restricting your arms during transitions.
Fleece: insulation that keeps pace with your effort
A fleece is generally the easiest layer to keep on during sustained activity in cool weather. It traps an insulating layer of air while remaining breathable. Its benefits are particularly clear when your pace varies: brisk walking, approach hikes, cold-weather trail running and hikes with short breaks.
The KOKANEE is designed as an active midlayer. Wear it as a mid-layer over a breathable base layer, then add weather-protective outerwear if wind or rain sets in. A fleece does not replace a hardshell: it manages warmth, not waterproofing.
Insulated jackets: warmth when your effort drops
An insulated jacket comes into its own when you stop, temperatures drop or you become more exposed to the elements. Carried in your pack, it can be a safety layer to put on at the summit, during a long break or before a descent. The key is not to wait until you feel cold before putting it on.
For active use, lightweight, packable insulation provides a buffer against the cold without weighing down your layering system. The BALTORO follows this approach, with insulation suited to mountain activities and changes of pace.
Gilets: a highly effective option for transitions
A gilet concentrates warmth around your core while leaving your arms free. It is a good choice when your body needs extra insulation without the feeling of a full layer during brisk walking. It is particularly useful when you get moving again soon after a break, or when temperatures are cool rather than bitterly cold.
A simple rule for choosing
- You stay active and sweat regularly: fleece.
- You expect a long break, a summit, a descent or very cold conditions: insulated jacket.
- You want to regulate core warmth during transitions: gilet.
The right insulation also depends on your outer layer
Insulation works as part of a system. Under a hardshell, it retains warmth more effectively because wind and moisture are kept out. Without an outer protective layer, an insulated jacket or fleece may not be enough once the weather deteriorates. Explore this approach in our guide to cold weather, insulation and common mistakes, as well as our three-layer system guide.
Care and longevity
Well-maintained insulation performs at its best. Follow the garment’s washing instructions, dry it properly and favour repairs for non-critical snags that do not affect its use. Our Repair Rather Than Replace approach helps extend the life of your gear.
In summary
Fleece for movement, an insulated jacket for reliable warmth, a gilet to regulate warmth during transitions: rather than looking for one piece that does everything, build an insulation system suited to your activity level and the conditions you expect.