How to test your fabric

It’s always a bit of a gamble when you go off-label and ignore a manufacturer’s advice. “Generally certain things should be able to withstand hand washing,” Ms. Young said. “But that doesn’t always translate into everything going well.”

To lower the risk, the experts suggest testing your fabric to check for warping and color transfer. “Find an inconspicuous area on the garment, like the side seam or hem, and dip it in water,” Ms. Boyd told us. “If you notice any sort of distortion, we don’t recommend washing.”

Ms. Young said she used a similar method to check for dye transfer: “Place a white paper towel on each side of the dampened area and press down. If any color is seen on the paper towel, the item isn’t colorfast.” And, she said, the more colorful your garment, the bigger the risk. “When it comes to silk, dark and brilliantly-colored pieces and patterns are best dry cleaned.” Patterns with contrasting colors are especially susceptible to damage, as any leaking dark dye can easily stain the lighter areas.

Another clue? The price. As Ms. Young explained, cheaper, low-quality silks are often less stable than the expensive stuff, so they don’t do as well with hand washing. “A good test for silk items is to gently bunch it into a ball with your hands, then release. If the fabric feels luxurious and liquid, it likely will do fine with hand washing. If it creases and wrinkles badly, send it to the dry cleaners.”

When must you dry clean?

“There are some fabrics that react poorly to water like viscose, a type of rayon,” Ms. Boyd said. “Although many rayons can be washed, viscose has been known to shrink to extreme proportions.” Similar fabrics in the rayon family include lyocell (known by the brand name Tencel), modal, and cupro (often branded as Bemberg), although these are usually washable. “The important takeaway about rayon is to follow the care label,” Ms. Young said.

Remember, if your item has a blend of fabrics (or two different fabrics, as in a coat with a lining), always clean according to the more finicky one. You may be able to hand wash silk, but since viscose usually requires dry cleaning, you shouldn’t wash a silk-viscose blend at home.

No matter the fabric content, when the label for an item with a decorative finish (such as moiré or pleats) or delicate beading recommends dry cleaning, don’t ignore it — those details are very easy to ruin. If you have something particularly sentimental or fragile, playing it safe may be the better option. “Generally, it’s often fine to hand wash silk. For very special pieces, you may still want to opt for a dry cleaner,” said Ms. Harrington.