How tight should a waterproof jacket be?
A waterproof jacket should fit snugly without restricting your movement. When trying one on, move around: jump up and down, wave your arms around, and twist your body. You want to make sure you have full range of movement available to you.
Fit and cut
Most types of rain jacket for hiking are sized to fit over mid layers, so it's usually unnecessary to size up unless you anticipate using your jacket in extremely cold climates and wearing a bulky insulating layer like a beefy down jacket.
Don't forget to look at how the jacket wears at your neck, hands, and waist as well. Cuffs should be adjustable so rain doesn't run down your sleeves. It should be tight, but comfortable at the neck so you don't get water down your back. And it should be reasonably tight at the waist without restricting your hips.
Fit The fit should encourage layering underneath, but shouldn't be too loose. Remember that you should be able to cinch your rainwear down so it's snug enough if the weather turns.
Typically, you will wear a raincoat overtop of a sweater, suit jacket, or cardigan. As a result, you should purchase a raincoat that is slightly larger in size and leaves room for your to layer your clothing underneath. This will allow you to stay warm and dry during rainy weather.
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Find your chest size, like you would for a shirt, knitwear or pyjama top. Measure around your fullest part. The tape measure should be under your arms. The next step is to find your sleeve length, this is measured from the base to your neck to your wrist.
Stand in front of a mirror and look for signs that the fit isn't right. If the sleeves don't cover your wrists and the bottom of the coat rides up — like the image on the left — the coat is too small.
Trying on Jackets in a Store. Opt for a jacket that's 1 size larger than your shirt size. This is the general advice for buying a jacket so that it won't be too tight. Having the jacket a little bigger than your normal size will also help to ensure that you can easily layer it over other items.
Fit. A down jacket should not be too fitted or too loose. You should allow for adding layers underneath but ensure it's not too roomy as cold air could get in through the hem and arms.
How do rains jackets fit?
Generally the Unisex raincoats are loose-fit and a half size larger than normal clothing while the Womens raincoats matching your normal clothing size. This can vary though, so go after the largest measurement that fit you for the most comfortable fit.
Condensation and perspiration are the primary reasons that you can get wet inside a raincoat. Condensation occurs when water vapor touches a colder surface, like the inside of your rain jacket which acts as a thermal envelope keeping colder external air from chilling you.
Buy a Size That Fits Your Wardrobe
“We often encourage guys to size up when it comes to outerwear. If your coat is snug with a blazer or a sweater underneath, you should go for a bigger size. If the sleeves are too long, you can always get them tailored.
Trying on Jackets in a Store. Opt for a jacket that's 1 size larger than your shirt size. This is the general advice for buying a jacket so that it won't be too tight. Having the jacket a little bigger than your normal size will also help to ensure that you can easily layer it over other items.
If you're used to buying tailored clothing from US retailers, you'll know that your suit jacket size should roughly translate to your chest circumference as measured in inches. For a slimmer fit, choose a jacket size ~1″ smaller than your (body measurement) chest circumference.