Understanding Breathable Jackets

September 10, 2021

We’ve all experienced wearing a rain jacket or any water-resistant jackets while walking down the street on a rainy or wet afternoon.

And it doesn’t take long for us to feel stuffy or sweaty inside our coat even if we feel chilly on the parts of our body that are exposed. It’s a polarizing feeling to feel uncomfortably hot in some parts and cold on others. We often attribute this to our coat’s lack of breathability. When moisture from the inside gets trapped, due to the absence or lack of breathability, it builds which results in a cold or sweaty feeling inside.

It is important to choose the right jacket to wear on the activities you’re planning to do. A suitable apparel will give you the right comfort and protection for when you go outside and be exposed to the elements. Having adequate breathability on your long rain jacket will allow moisture from the inside to escape thus giving you comfortable wear while keeping yourself dry. A lightweight water-resistant rain jacket is essential for places where it often gets wet as well as for seasons when rain is a common occurrence.

What is Breathability?

As mentioned, breathability is an attribute of a fabric that allows vapor generated inside to get out. It can be measured in many ways, but it is common to see manufacturers use the Moisture Vapor Transmission Rate or MVTR. This is the amount of water vapor that seeps or goes through one square meter of fabric for 24 hours.

It uses grams/meter/day to determine the breathability and the suitable uses or activities that can be done with the fabric. Since the test is using one square meter for a period of one day, we will be able to differentiate using the amount of water that passes through.

If the rate is >8,000 g, it means that there is an adequate level of breathability and it’s good for any outdoor activities.
If the rate is >20,000 g, it has ample levels of breathability to allow you to do more activities.
If the rate is >30,000 g, this level will give you more comfort for aerobic exercises or activities.

There is also another way to measure the fabric’s breathability, this is the Resistance to Evaporative Heat Loss or RET. This method indicates that a lower number means more breathability.

A RET of >4 means it gives you more comfort to do aerobic exercises
A RET of >6 means you have breathability for a number of activities
A RET of >9 means the fabric is meant for general outdoor activities.

Important to Remember In Garments

Since the test is done on a single layer of fabric, it can get a little tricky when it comes to garments that have folds and pockets. The design can affect the total breathability because an additional layer diminishes the rate or increases the RET of the area. One way to solve or mitigate this is the use of mesh fabric for the inside pockets. Although the mesh doesn’t have the desired durability for certain items in our pockets it helps in keeping the overall MVTR rate of the garment consistent all throughout.

Now that you’re familiar with the aspect of the breathability of your jacket or coat, you can be mindful of the products or options you’re going to choose from. This might not seem critical at all when you’re in the dressing room or just browsing through the web, but when the time comes for you to actually wear the jacket, you’ll feel the difference.

When it comes to rain jackets, our priority is the water-resistance, but we cannot also disregard the comfort especially if we are doing physical activities outdoors.