I’m looking for a new pair of hiking shoes, and some of the ones I see are both waterproof and ventilated. Like these. The description includes the line “Waterproof membrane treated with Aegis® antimicrobial solution provides impermeable but breathable barrier.”
So . . . how can a shoe be both waterproof and ventilated?
Goretex. Amazing stuff.
From Randy’s link: “Each pore is approximately 1/20,000 the size of a water droplet, making it impenetrable to liquid water while still allowing the more autonomous water vapour molecules to pass through.”
If you go with a breathable waterproof boot (e.g. Goretex or any number of similar products), be sure to regularly apply a durable water repellent to the outside of the boot, for if the outer fabric of the boot becomes saturated with water, then the moisture on the inside of the boot will have nowhere to go.
Won’t the water repellant clog the pores?
Not if you use the right stuff. Have a look at the Nicwax line. A good DWR should stick to non-water repellent surfaces (e.g. boot exterior fabric or leather), but not stick to water repellent surfaces (e.g. Goretex membrane), thereby preventing the fabric from becoming sodden without affecting the Goretex’s pores.
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