What air permeability means in clothes
Short answer: Air permeability describes how easily air passes through a fabric. It is measured in a laboratory and says something about how open the fabric is, but it is not the same as how comfortable clothes feel. The amount of air is only one piece of the picture.
What air permeability means in plain words
Imagine blowing through a piece of fabric. If the air passes easily, the fabric has high air permeability and may feel light and airy. If hardly any gets through, the fabric is denser and may hold warmth better, but can also feel stuffy when you move.
How it is measured
In a laboratory a piece of fabric is clamped into a machine that draws air through it under set conditions. Then they look at how much air passes in a given time. The result can be compared between fabrics, but it does not tell you everything about how a finished garment feels on the body.
Air permeability is not the same as breathability
Breathability also concerns how the fabric handles moisture and vapour from the skin. A fabric can let a lot of air through and still feel clammy if it does not take up moisture. Conversely a denser fabric can feel comfortable if it absorbs and releases moisture. That is why air permeability is only one of several factors.
Weave, knit and thread
The structure of the fabric has a big influence on how much air gets through. An open knit and a loose weave let more air pass than a dense fabric with thick threads. The thickness of the yarn and how tightly it is spun also play a part. You can often feel this by holding the fabric up to the light.
Why wind and cold change the picture
When it is windy and cold, you do not want air to go straight through your clothes. A denser fabric is an advantage here, and an extra outer layer makes the difference. When it is warm and still, an open fabric is more comfortable because the heat is not trapped close to the body.
Layer upon layer
When you wear several layers, the air between the layers becomes part of the insulation. An open inner layer and a denser outer layer can give a good balance, so you can adjust to the weather. That makes the air permeability of any single fabric matter less than you might think. See bamboo training clothes for women for ideas on layering.
What to look for in summer clothes
On warm days a light, open fabric and a relaxed fit are often comfortable. Try bamboo shorts for women for the hottest days, and choose a women's long-sleeved bamboo T-shirt if you want to cover your arms without getting too warm. Fit matters as much as fabric.
Washing and wear
After many washes a fabric can change, becoming denser or more open depending on how it is treated. Gentle washing and low heat help the knit keep its shape. Always check the care label, and remember that quoted figures apply to new fabric, not after many washes.
Frequently asked questions
What is air permeability
It is a measure of how easily air passes through a fabric. It is measured in a laboratory under set conditions and can be compared between fabrics, but it does not tell you everything about how clothes feel.
Is high air permeability always better
No. On warm days it is pleasant, but in cold and wind you want a denser fabric. What is right depends on the weather and on what you are doing.
Does it mean the same as breathable clothing
Not quite. Breathability also concerns how the fabric handles moisture. Air permeability is only one part of the picture, and fit matters a great deal too.
