Field Guide
How to care for fabric, by fiber
Almost every laundry disaster comes down to one thing: treating a cloth as if it were made of a different fiber. Heat that presses cotton crisp melts polyester; the wash that refreshes a linen shirt felts a wool sweater to half its size. Care follows the fiber, so once you know what a cloth is made of, you know how to keep it.
The table below is the short version: how to wash, dry, and iron each fiber, and the single mistake that does the most damage to it. Each fiber links to its full entry in the catalogue.
The one rule
Heat is the enemy of most cloth. It shrinks the naturals, felts wool, and melts the synthetics. When you are unsure, cold water and low or no heat is almost never the wrong answer.
Care by fiber
| Fiber | Wash | Dry | Iron | Watch out for |
|---|---|---|---|---|
| CottonCellulosic | Warm or hot, any cycle; tough and machine-friendly. | Tumble dry; expect shrinkage if it was not preshrunk. | Hot, with steam or damp. | The first hot wash shrinks it; it wrinkles readily. |
| LinenCellulosic | Warm to cool, gentle. | Line dry or tumble low; it softens with every wash. | Hot while still damp for a crisp finish. | Creases hard and can shrink; do not over-dry. |
| RayonCellulosic | Cold, gentle or by hand; it is weak when wet. | Line or flat; reshape, never wring. | Low to medium. | Shrinks, stretches when wet, and water-spots. Viscose and modal behave the same. |
| SilkProtein | Cold hand wash with mild soap, or dry clean. | Roll in a towel, then dry flat out of sun. | Low, inside out, while slightly damp. | Water spots, sun fading, and deodorant or sweat. |
| WoolProtein | Cold, hand or wool cycle, or dry clean. | Lay flat and reshape; never tumble. | Low with steam, through a press cloth. | Heat plus agitation felts and shrinks it; moths. |
| AcetateManufactured | Dry clean, or cold hand wash very gently. | Dry flat, away from heat. | Very low; it melts easily. | Acetone, the solvent in nail polish remover, dissolves it. |
| PolyesterManufactured | Warm, normal cycle; genuinely easy care. | Tumble low to medium. | Low; it melts at high heat. | Grabs and holds oily stains; static and pilling. |
| NylonManufactured | Warm, gentle. | Low heat. | Low, or skip it. | Heat-sensitive; greys and yellows over time. |
| AcrylicManufactured | Warm, gentle. | Low heat. | Low. | Pills heavily, holds static, softens in heat. |
| SpandexManufactured | Cold; skip chlorine bleach and fabric softener. | Air dry or low; never hot. | Do not iron. | Heat and chlorine destroy the stretch. Almost always blended. |
Washing a fabric you are unsure of
No label, or not sure it is honest? Default to the gentlest path and work up.
- 1Identify the fiber. If there is no label, a burn test or a feel-and-water test will tell you the fiber family, which decides everything that follows.
- 2Test for colorfastness. Dab a hidden spot with a damp white cloth. If color lifts onto it, wash cold and alone, or send it to be dry cleaned.
- 3Start cold and gentle. When in doubt, cold water on a gentle cycle is the safe default for nearly every fiber. You can always wash warmer next time.
- 4Keep the heat off. Air dry, or use low heat. Heat is what shrinks the naturals, felts wool, and melts the synthetics.
- 5Reshape and dry flat. For knits and anything with give, lay it flat and reshape it rather than hanging it, which drags the cloth out of shape.
Why the three families need different care
The care table is long, but the logic behind it is short. Fibers fall into three groups, and each group fails in its own way.
- Cellulosic fibers, cotton, linen, and the wood-pulp rayons, are strong and take water and heat well, but they shrink, and rayon turns weak and stretchy while wet.
- Protein fibers, wool and silk, are the delicate ones. Wool felts under heat and agitation; silk water-spots and fades. Both want cold water and a soft touch.
- Manufactured fibers wash easily but melt under a hot iron or dryer, build static, and, in polyester's case, cling to oils and smells.
When to dry clean instead
Reach for the dry cleaner when water itself is the risk: tailored and structured garments whose canvas and linings would pucker, most acetate, and pieces where a dye is likely to bleed. Plenty of wool and silk labeled dry clean will hand wash safely, but the label is the maker's bet, not yours, so test a hidden spot first and accept that you own the result.
Common questions
Can you wash wool, or does it have to be dry cleaned?
You can wash most wool in cold water by hand or on a wool cycle, with a gentle detergent, then lay it flat to dry. What ruins wool is the combination of heat and agitation, which mats the fibers into felt and shrinks the garment. Tailored or structured wool is better dry cleaned to protect its shape.
How do I stop cotton and linen from shrinking?
Most shrinkage happens on the first hot wash. Prewash the fabric before you cut and sew, or wash the finished garment cool and dry it on low. Once a natural fiber has been through a hot cycle once, it has mostly done its shrinking.
What does dry clean only really mean?
Sometimes it means the fiber or construction cannot survive water, as with most acetate and many structured or lined garments. Often it is caution: a maker labels dry clean to avoid blame for a careless home wash. Silk and wool frequently wash by hand fine, but test a hidden spot first and accept the risk.
Why does my polyester hold smells and oily stains?
Polyester is oil-loving and water-hating, so body oils soak into the fiber while water struggles to flush them out. Wash it promptly in warm water, skip the fabric softener, which traps odor, and treat oily marks with a little dish soap before washing.
How do I care for stretchy elastane or spandex blends?
Wash cold, skip both chlorine bleach and fabric softener, and air dry or tumble on no heat. Heat and chlorine break down the elastic fibers, which is why leggings and swimwear bag out and lose their snap after hot washes or a chlorinated pool.
Keep going: identify a mystery fiber, the fibers in the catalogue, or the rest of the field guide.
Sources & References
- Laundry symbol, Wikipedia
- Dry cleaning, Wikipedia
- Best Detergent for Delicate Fabrics: Cashmere, Silk, Wool & Linen, Mozi Wash