The Science of Layering

I recently started working for an outdoor retailer and I love it! Not much beats getting to exchange stories of adventures and geeking out over gear with like-minded people! Since winter, the best season of all, is upon us the first thing I was trained on was outerwear. So I figured I’d share some of the tips I’ve learnt for helping others find the right jacket/layering system for them.

A solid layering system is the bee’s knees when it comes to keeping yourself warm. You don’t want to lose heat because you don’t have enough insulation or ill-fitting layers. Heat loss occurs through 3 different ways: evaporation (when your skin stays wet), convection (heat moving away from our bodies), and conduction (touching cold things). It is important to keep those in mind when picking your layering system. There are three parts to consider: baselayer, midlayer, and shell.

  1. Your baselayer comes first, it should be fitted against your body but not so much so that it restricts movement. Make sure it is long enough. It’s not fun having a base layer that lets in that cold air on your lower back! The base layer is what begins the moisture wicking process that helps keep you dry and warm. It does so by pulling the sweat away from your skin and dispersing it across the fabric in order to allow the fabric to dry faster and to begin transporting moisture to out the outer layers away from your precious skin! Yay base layers!
  2. Next comes your mid layer! This insulating layer(s) can take many different forms. It can be a down jacket, a fleece, a synthetic layer or wool. Super important in keeping you warm. So, since there’s so many options, which type of insulation should you go with? Well that’s where a little bit of personal preference and intended use comes in.
    Down is commonly known as the warmest type of insulation (for good reason!). It is generally lighter and packs smaller making it very attractive to those pursuing hiking. When selecting a down jack you want to look at its loft and its weight in order to determine how warm the jacket will be. A jacket’s loft is the thickness of down within the jacket, but a higher loft does not necessarily mean a warmer jacket (heavier jackets will be heavier). If down gets wet it’s not great at keeping you warm and continuing that moisture transportation and is an absolute pain in the butt to get completely dry. So ultimately you have to weigh the pros and cons.
    So some might go for another option. Enter synthetic layers. These are also quite effective at keeping you warm. Although they tend to be a bit bulkier (but not always), they are able to keep you warm even while they are wet! A fleece is my go to midlayer on cool days spent on the water kayaking or canoeing because I know it will keep me warm when I inevitably get soaked. Synthetic layers are also excellent at continuing that moisture transportation. Super handy indeed!
  3. Midlayers can double as an outerlayer but when the rain and heavy wind sets in – enter the shell! You wouldn’t want to lose all the heat your body just produced due to the weather. A good shell should be water proof (or resistant in some cases) and breathable. It should complete the moisture transportation process expelling that pesky water into the outside world.
    There are a few different technologies that you can find in a shell. A popular pick is a laminate (such as Gortex). This basically means there’s a membrane sandwiched between two protecting layers and laminated together. Laminate shells are good at letting that moisture out without letting that rain in. Another means of waterproofing is DWR which is a chemical that adds microscopic fibres which causes some beading action for water molecules. There’s something very satisfying about watching water droplets roll right off of your jacket. Shells are also good for keeping heat in so on those chilly nights your rain gear can act as some extra insulation!

Did you know that the more insulation you keep on your core, the warmer your extremities will be? And NOBODY likes having cold hands and feet. So it is super important to find a layering system that works for you!

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