Ever since Gore-Tex revolutionized raingear in 1973 with the first waterproof/breathable membrane, fabric engineers have been working to improve the breathability half of the equation. As every overheated hiker knows, more is definitely better. And while we’ve seen many incremental advances over the years, nothing compares with the windfall of 2011. W.L. Gore, Polartec, Mountain Hardwear, and Columbia all launched new outerwear lines that employ thinner, more porous waterproof membranes combined with advances in fabrics and laminating techniques that further enhance breathability. The result? Our field testers report that the best new shells are 20 to 30 percent more breathable than anything they’ve used before, meaning you can stay comfortable while working harder in a greater range of conditions. And if you do overwhelm one of these jackets on a hard summit push, sweat disperses—and midlayers dry—faster. So which one’s the best?
We studied countless pages of lab data supporting each brand’s breathability claims (they all tout different test methods, see below), plus dense workbooks detailing the materials and construction methods. The graphs and wonky verbiage provided valuable background, and we’ve summarized the key claims made by each manufacturer in the individual jacket reviews. But as every backpacker knows, you can’t mimic an Arctic maelstrom in a lab. And the breathability of any jacket only starts with the membrane. Real-world performance comes from the sum of the parts, including the breathability of the liner and face fabrics, the glue patterns used to bond it all together (glue doesn’t breathe), and the effectiveness of the DWR (durable water repellent) treatment. The DWR performance is key because it causes water to bead up and roll off; if the fabric becomes saturated, the water itself forms a non-breathable layer.
So we set the graphs aside and put the new shells through four months of hard field testing. By the end, we’d narrowed the field to these four standouts. They each proved extremely close in terms of breathability (scores are for the whole jacket, not solely the membrane), so base your pick on the total package, including features, fit, and packability.
Most Breathable: Mammut Felsturm Half-Zip
Most Versatile: Westcomb Apoc
Most Durable: Mountain Hardwear Jovian
Best Value: Columbia Peak 2 Peak/Peak Power