Keeping Warm and Dry in the Cold and Wet
Part Two: Insulation, Skin Layers & Extremities
If you aren't fashion conscious you can find budget insulation everywhere.
Except for Thinsulate(tm) and other boundary layer materials most common in gloves, boots and fashion clothing about twice as warm for thickness as down and roughly equal for weight, it is the thickness or loft of the skin-level layer of your layer of still, body- warmed air, not the material, which keeps you warm.
So check the thrift shop for old cashmere or angora sweaters that maximize loft per weight. Even ratty looking, out at the elbows sweaters work. Down and loose fills work too, but baffled construction costs more than pile fills which sew together. Down also costs much more than artificial fills and won't insulate if soaked. Mess about water long enough and everything does get soaked! Wool insulates even if wet, but is so heavy when soaked, and takes so long to dry that it's no longer the choice except in oiled sweaters which absorb little water, and for masochist winter Finn class racers who soak up water to increase their weight to reduce capsizing.
High-tech fleece and pile garments which layer without excessive bulk handle the insulation for active users in most conditions. While neither waterproof nor windproof, they dry fast and hand wring to near dry if you fall in. Combine a pile vest and a pile zip-front jacket and you solve most insulation problems. As usual check the zipper for even stitches and make sure that any elastic cuffs dry reasonably quickly. The only drawback of fleeces and piles, aside from a trend to trap body odor, is their transparency to wet and wind-chill. So when you wear them as outer layers, tote a windshell.
Piles from makers like Patagonia are a good top-end choice; as a rule price is a fair guide to quality in this area. Gear for ice climbers, it should be noted, works very well for ice fishing and winter steelheaders too. Try progressively warmer and thicker Polarlite(tm), Polarfleece(tm) plus tough Polartuff(tm) and other new materials which absorb little water and, indeed, wick water off your body so you feel dry. Below 95 percent humidity, body warmth vaporizes this moisture, which is either transpired through the outer fabric or in boots, pumped up and out by body movement.
However, if the outside humidity is 100 percent, and the humidity at the skin level and in your garments reaches 100 percent, you stay wet until the humidity drops or you flee to air-conditioning. Note that woven materials offer design advantages as they do not require the baffles and complex designs needed to contain loose fill insulation.
In fills, materials such as Thinsulate(tm), an extra dense fiber, work well where bulk is a problem. These materials dry quickly because they do not absorb water. Class five flotation vests and jackets in Airex (tm) and other soft foams make superb insulation and are quite comfortable, so they are much more likely to be worn than bulky jackets. If you do fall in, flotation vests and liners slow hydrothermia. Such jackets and vests also suit stream anglers on winter waters and big water anglers anytime.