In the world of lightweight down products you often see manufacturers highlight specifications for the nylon fabric used. It can be a bit confusing at first, but good to know so you get the right gear for the right purpose.
Denier (d) is the weight of the single strain of nylon fabric used. This is based on the weight of a 9,000 meter long thread in grams. The baseline is silk that has an average weight of 1 gram per 9,000 meters! Today’s light technical down jackets and sleeping bags has a Denier of approximately 10 to 20d. However, the lighter the fabric, they easier it is for getting tears and punctures.
Just like it sounds it is measured by counting the number of threads contained in one square inch of the nylon fabric or one square centimeter. Which includes both the length and width of threads. The thread count is the number of threads counted along two sides (up and across) of the square inch, added together. A high thread number is often believed to be a higher quality fabric, but around 400T is as high as this goes.
Ripstop (also known as plaid fabric)
Ripstop fabrics are woven nylon, using a special technique that makes them resistant to tearing and ripping. During weaving, reinforcement threads are interwoven at regular intervals in a crosshatch pattern. The intervals are typically 5 to 8 millimeters. You can see this feature if you hold up the fabric against the light and the small squares become apparent. Ripstop is usually used in parachutes, hot air balloons, tents, sails and kites but also sometimes used in sleeping bags.
Taffeta (also known as plain fabric)
Taffeta is typically used as the sleeping bag or quilt lining. It’s softer than ripstop so has a more comfortable touch to your skin. When you hold this fabric towards the light, you will only see a plain surface. This material is also very shiny, making it popular for luxury down jacket manufacturers.
So what should I choose?
This depends on what you are planning to use it for. If you need a strong sleeping bag or down jacket for a longer trek, then a bit heavier ripstop material should be used to withstand the elements better. However, if you want a very soft and comfortable touch, then a lighter taffeta material is for you, like the popular Cloud Series quilt.