How to stop your T-shirts from shrinking in the wash

Once you understand what's happening at the microscopic scale, t-shirt shrinkage becomes a lot easier to predict and prevent.

In essence, stretching is a part of the thread manufacturing process. The heat and movement inside a washing machine can actually destroy the tension that has been put into the threads, making them revert to their natural, denser state. If that happens over the whole t-shirt, these microscopic changes multiply into inches in diameter and length.

The care label should contain important information about the fabric and washing instructions. Pure cotton shirts generally shrink more than polyester blends, so be extra careful if that applies to your tee. If the label says 'pre-shrunk', however, the manufacturer has already treated the fabric, so you can usually wash it at a higher temperature, although some shrinkage may still occur.

Washing machines have temperature options for many reasons, but one of them is that cold water cycles reduce shrinkage. The cold setting keeps fabric integrity while still removing everyday dirt and sweat. A warm (not hot) wash is OK for particularly soiled items. After all, if the item is unwearable because of the dirt, you've nothing to lose by giving it a go.

Washing powders and capsules are also getting better at washing at lower temperatures. Choose detergents formulated for cold water washing. These products often contain enzymes that clean effectively at lower temperatures. Avoid using excess detergent, though, as it can stiffen fabric, contributing to wear.

High-speed spins and vigorous washing stretch and stress fabric fibres. Select the gentle or delicate cycle for your t-shirts whenever possible. This reduces physical wear while still cleaning the clothes properly. This rule holds true for almost all your washing - try gentle first, and only get more intense if stains remain.

Of all the parts of the washing process, the dryer is most responsible for t-shirt shrinkage. Air-drying eliminates this risk, so plan ahead and don't wash the tees you intend to wear that evening. Hang shirts on a washing line outdoors or on a drying rack indoors. If you must use a dryer, choose the lowest heat setting, remove shirts while slightly damp, and finish drying on a hanger. You probably don't need to iron your t-shirts most of the time, but use a low-temperature, gentle setting if you do.

For t-shirts that have already shrunk, soak the garment in lukewarm water with hair conditioner for 30 minutes. Gently stretch the fabric while damp and lay them flat to dry with weights at the edges. This sometimes restores shape, though results vary based on fabric type and amount of shrinkage.