Monday, November 10, 2008

Understanding "Waterproof/Breathable"

As we begin to settle into our rainy season, many of you are looking to protective outerwear to get you through the day, and night. There are many different technologies when it comes to water repellent fabrics, from simple rubber or waxed cotton or wool for that matter, to high-tech, waterproof/breathable membranes. Many of you can recall childhood memories of sweaty raincoats and galoshes; they kept you dry alright, until so much of your sweat collected inside that you were as wet as you would have been without the rubber layer. By choice and nostalgia, we often return to that familiar clammy feeling for fun, or fashion, but when we need to stay dry, inside and out, we look to modern technology in the form of waterproof/breathable membranes.















How do these membranes work? The quick answer is that they prevent exterior moisture from entering while allowing interior moisture to escape. Typically waterproof/breathable membranes have a pore structure that keeps rain out while giving our sweat a path of least resistance to the outside world. Footwear and outerwear that use waterproof/breathable membranes need a special construction process that guarantees the membranes work as intended, known as "seam-sealed" construction, which means anywhere there is a stitched seam, that seam gets "sealed" with a special seam tape which maintains the integrity of the membrane.

Almost everybody is familiar with the name Gore-Tex, as it has become the household name in waterproof fabrics. Started thirty years ago in 1978, Gore created the first product that took us from the waxed cotton and rubber era and ushered us into an era where fabrics started to mimic our own bodies natural evaporative heat-loss process. Gore-Tex is still synonymous with the idea of "waterproof" and as a brand, is instantly recognizable--when we see the Gore-Tex tag on products we know it means that we're going to stay dry. However, there are other choices when it comes to waterproof/breathable fabrics, such as eVent, Keen Dry, 3XDRY by Schoeller, Sympatex, Membrain, and others, all of which are equally adept at keeping moisture out, while doing their best to move moisture from the inside out.


The biggest challenge in waterproof/breathable membranes is the "breathable" part, with the ultimate goal being to wick moisture away from our skin and move it through the fabric to the outside environment, and each company approaches this process differently. Some, as with eVent, use a micro porous membrane with "millions of tiny pores" to achieve this, allowing interior moisture to vent directly to the outside. Schoeller uses what they call 3XDRY, which is a water repellent exterior, a moisture absorbing interior, and a sandwich layer that disperses the collected interior moisture over a large surface area to evaporate it quickly. And Gore-Tex utilizes a pore structure that is smaller than a water droplet, but larger than moisture vapor to wick moisture away from your body and transport it through the membrane to the outside.


However, the challenge in moving moisture from interior to exterior environments is dependent upon the relative humidity levels on both sides of the membrane. The drier the exterior environment, the faster the membrane will move moisture out, the wetter the exterior environment the slower the membrane will move moisture out. At the same time, the amount of moisture (sweat) being generated (based on activity levels) will determine the amount of moisture needing to be vacated to the outside world, and if the outside world has 100% humidity then the membrane won't be able to move moisture very quickly. So, if you're engaged in a high aerobic activity and its raining cats and dogs, don't expect your waterproof/breathable to keep you feeling like a summer day inside, but if you use your waterproof/breathable for getting to and from work, trips to the grocery store, or a leisurely stroll through a downpour, then set your expectations high, because modern membranes do the trick.
In the end, we are a far cry from the waxed cotton and rubber boot days, and we expect our performance fabrics to, well, perform. And they do indeed perform, as long as we are understanding of their current limitations. So, if you're standing in a puddle and you want your feet to stay dry, look to almost any waterproof/breathable footwear to do the job, but then you might want to ask yourself, "why am I standing in a puddle?"

Market Street Athlete

Tuesday, November 4, 2008

Neighborhood


It has been almost a year since we opened, and we're having a great time on the other side of the street. Market Street that is. In Ballard of course, and across the street from Market Street Shoes, our parent, or sister, store. Market Street Athlete was born of community requests for a place to find athletic footwear in the neighborhood. "In the neighborhood", because shopping locally matters to you, because having to go to the mall, or downtown, or Greenlake for that matter, is not what most of you would like to have to do for a new pair of running shoes, or hiking shoes, or cleats, or...well, you get the point. "In the neighborhood", because this is where we live, work, and play. Because this is where we bring our friends and relatives when they come to visist, to the Locks, to Golden Gardens, to Discovery Park, to the Farmer's Market, to dinner, for a stroll through the fall leaves, or a run through the crisp morning air, or a hike through Carkeek Park (because it hurts our pocketbooks to get to Mt. Si.) Because we raise our kids here, we learn here, we start careers here, we retire here, and we grow old here. This is our neighborhood, the quality of which is a result of what we all bring to it, and we are rewarded with an enviable community, a Neighborhood, that we call... Ballard.


See you in the Neighborhood