Whether you are the type of person who is always cold or has a comfortable body temperature at all times, the fit of a coat plays a big role in its thermal effectiveness.
One of the most important things you can do to ensure that you enjoy the winter season is to have a winter coat that will keep you warm and comfortable.
LET YOUR COAT BREATHE BEFORE YOU WEAR IT
If you order a coat online, it will most likely arrive at its destination packed in a bag or box that has been compressed to fit. Just like a new comforter or down sleeping bag that has just come out of its compression bag, you need to give them time to breathe and expand again. This will allow the insulation to move through the fabric and fit properly in relation to the shape and/or fit of the product in question.
The same is true for a new coat. Whether it's a down parka or synthetic insulation, let it breathe for a few hours (or even a day) to restore its shape. Hang it on a rack and let it expand again in the closet. That way, you'll know you'll look fabulous, just like your coat, when you pull it out to show it off to your friends.
To provide warmth, the air inside the coat must be able to circulate, and the same goes for your gloves or mittens. If you have a pair of gloves or mittens where your fingers are touching the ends, you will most likely get cold fingertips because there is no room for air to circulate to create heat.
Good and bad air pockets
Whether the parka you're wearing is insulated with down, synthetic insulation or fleece lining, good air pockets give air room to circulate and create warmer air.
When I say air pockets, I don't mean big folds in excess fabric. These are called bad air pockets because they leave too much room for air to circulate, which means the coat can't warm up effectively. Imagine a large lake versus a small lake, the small lake will warm up faster since there is less surface area to heat compared to the large lake.
Think of good air pockets as small pockets found through fabrics and particles used to insulate your coat.
Bigger is not always better
Compared to a coat that fits like a glove, one that's too big won't be effective at insulating and will force you to wear many layers underneath.
IF IT'S TOO TIGHT, IT'S A FAILURE
If the coat you're wearing is too tight in certain areas of your body, such as your armpits, the down or insulation will be compressed and won't have enough room to expand and keep you warm.
The particles and materials used to create the insulation in your coat are made of mini air pockets that trap air and warm it. When these particles or materials are compressed, there is no space left for the little pockets to accumulate air and insulate the coat. The space that these pockets take up is where the heat accumulates, so without them you will be cold and uncomfortable.
A parka that is too tight can also affect your mobility. The best way to check if you've chosen the right coat size is to perform a few small tests. These four tests are simple enough that you can try them on in the comfort of your own home or in the fitting room.
THE HUG TEST
Unless you're a robot or the tin man from the Wizard of Oz, your body needs to move and not just a little! In the course of a day, your body is constantly moving in various ways. Whether it's flipping off a cab to stop, buckling your seatbelt or filling your grocery bags at the market, you need some freedom of movement. If your coat is too tight around your arms or body, you'll have trouble with your daily routine.
This is where the hug test comes in handy. Put on the new coat, zip it up, and give yourself a big shoulder-to-shoulder hug. If you have trouble lifting your arms, the coat is definitely the wrong size. If you can do the hug test, but are tight around the elbows or shoulders, it might be a good idea to try the size up.
It can be heartbreaking to have a crush on a coat that is no longer available in the size you need, and then try to convince yourself that the size down might still fit if you wear a thinner base layer... But don't give in to being that person. If the coat doesn't fit, it won't perform to its full potential and you may have to buy a new one that will fit better and keep you warmer.
Keep in mind that when trying on a winter coat, it's better to try it on with a thicker cardigan or base layer than not enough. If the snuggle test is positive with just a t-shirt under the coat, give it another try with a cardigan underneath. When it's really cold in the winter - no matter how much insulation is in your coat - you'll probably need to add an extra base layer at some point, so keep that in mind when you try it on.