Insulating against the elements - natural down vs. synthetics

First know this: When dressing for outdoor activities in cold weather, your shell does not keep you warm. A shell protects you from the elements and it cuts wind, but when you really need to stay warm, look for insulation layers that help trap warm air against your body. Outdoor Research offers a wide combination of insulation layers made using different materials that cover any need—the big question is how to choose the right one. When it comes to choosing a layer for insulation, think about the weather conditions where you will be using the jacket and the intensity of your activity. If you’ll be doing more aerobic activities, such as Nordic skiing, ski mountaineering or ice climbing in colder conditions, choose a lighter insulating layer. If you’re trying to stay warm during stops or at lower exertion levels, choose a thicker one.

You will also need to consider the weather when you choose between goose down and synthetics. In very general terms, goose down excels in dry climes, while synthetics are a better bet for wet conditions. But your decision should also be based upon the bulkiness of the jacket and the materials in the jacket beyond the actual insulation.

The first thing to look at in a goose-down insulation layer is its fill power rating. Goose down provides warmth through its loft - its ability to trap warm air within its stringy filaments - and still spring back after being compressed. The higher the rating, the better the goose down will trap dry air. Outdoor Research uses goose down in the high-quality 650+ to 800+ range (to get scientific, those numbers indicate how many cubic inches fit in one compacted ounce of down).

The Maestro Jacket™ (800+ with a baffled construction), for instance, was developed for guides who needed a super-warm belay jacket. The Transcendent™ Collection for men and Aria™ Collection for women, meanwhile, are 650+ fill power jackets, hoodies and vests that work in a wide range of cold-weather conditions.

Synthetic insulation provides warmth akin to goose down, but retains the ability to hold in heat more effectively if it gets wet (on the flip side, it’s not as compressible as goose down). Goose down can clump together and lose its all-important loft when it gets wet. Synthetics don’t have quite the same toasty warmth-to-weight ratio as goose down but they offer a better choice in damp climates or potentially when you’re out for a longer duration. Synthetics are rated in gram weights—the higher the weight, the more insulation they provide. The Outdoor Research Neoplume Jacket™ and Neoplume Pants™ use light, water-resistant 60-gram PrimaLoft® insulation, making them ideal layering under a shell in damp weather. The Chaos Jacket™, meanwhile, uses 133-gram insulation in the body with WINDSTOPPER® on the face, making it well suited for alpine assaults.

Insulated shells, like the Chaos Jacket™ offer the best of both worlds — they confer all the protection of a breathable/water-resistant backcountry shell alongside the warmth of an insulator. The only downside is that you have fewer options in terms of adjusting layers, but in many situations, adding a waterproof fabric over insulation extends the usable range of a mid-layer for activities like resort skiing, sidecountry skiing or alpine climbing.

In the Outdoor Research line, the new Havoc Jacket™ was developed out of feedback from International Mountain Guides, out of Ashford, Wash., that adding a WINDSTOPPER® shell over PrimaLoft® substantially increased the breadth of conditions in which a light synthetic jacket could be used. Some shells in the Sidecountry ski line, such as the Axcess Jacket™ and StormBound Jacket™, go a step further and integrate insulation under a full waterproof/breathable shell.

The takeaway? Your insulator is the piece that keeps you, well, warm. Insulators come in a huge range of options that do everything from add to your layering to work as a do-it-all shell. Think about the activity and conditions to choose the right one—and it’s never a bad idea to have an extra warm, insulating layer in store just in case conditions deteriorate.