Here's Why You Should (Almost) Always Wash Your Laundry in Cold Water

Here's Why You Should (Almost) Always Wash Your Laundry in Cold Water

Washing your laundry in hot water may be an effective way to get dirty clothes extra-clean, but the environment (and your budget) could pay the price for it. One major problem lies in tiny plastic particles called microfibers, which can shed from your clothes and eventually end up in the oceans or our drinking water supply.

When you do a load of laundry (with hot water in particular), microfibers shed from synthetic fabrics like polyester and nylon into the water. Research says the average household in the U.S. and Canada releases 533 million microfibers (which is equal to about 135 grams) into the water system per year just by doing laundry.

That's a problem because wastewater treatment systems can't filter all of these particles out. In fact, microfibers contribute up to 35 percent of all plastic pollution in the oceans, according to Ocean Clean Wash, a campaign initiated by the Plastic Soup Foundation. These small plastic pollutants can be mistaken for food by ocean organisms and disrupt the natural ecosystem.

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What Are the Benefits of Doing Laundry with Cold Water?

There are a few ways to break the cycle of microfiber pollution, and washing your clothes in cold water is a good first step. One study shows that the amount of microfibers released during a cold-quick cycle (77 degrees F for 30 minutes) was significantly less than during a longer hot water cycle (104 degrees F for 85 minutes).

The type of clothing you buy also matters. "The best solution is to purchase high-quality apparel that resists shedding," says Michael Mattingly, executive director of clothes care at GE Appliances. "For example, knitted fabrics are better than fleece, and natural clothing fibers are better than clothes with synthetic fibers."

Reduced energy use is another reason cold water may be a more sustainable choice. Hot water requires much more energy per load, with about 75-90 percent of the total used going toward heating the water, says Mary Gagliardi, also known as Dr. Laundry, a senior scientist at The Clorox Company. That means switching to cold water can add up to some major energy savings. According to Energy Star, washing your clothes with cold water each time could save you up to $66 per year in heating costs.

Washing in cold water can help slow fading of colors and shrinking in fabrics.

—Stephen Hettinger

Cold water can also help your clothes last longer. "Washing in cold water can help slow fading of colors and shrinking in fabrics," says Stephen Hettinger, director of engineering in washer systems at GE Appliances. "Testing shows that warm water or hot water helps accelerate fading in darker colors."

Should I Ever Use Hot Water Instead of Cold Water?

It's important to note that hot or warm water is still recommended for some loads of laundry. "Anytime you've got something that's harder to get clean, like heavily soiled work clothes, linens and towels, bedding, socks, underwear, or white garments that easily show the dirt, that's a good time to select hot water," Gagliardi says. Hot water is also most effective at killing bacteria, so it's ideal when washing up after a household illness.

Anytime you've got something that's harder to get clean, like heavily soiled work clothes, linens and towels, bedding, socks, underwear, or white garments that easily show the dirt, that's a good time to select hot water.

—Mary Gagliardi

When using cold water, proper laundry practices are essential to get the best clean. Gagliardi recommends using a liquid detergent because powdered formulas may not properly dissolve in cold water. Additionally, she suggests pretreating stains before washing and taking care not to overload the machine.

It's also worth noting that all cold water washes are not created equal. "Washing with tap cold in Minnesota in January is very different than washing with tap cold in Florida in the summertime," Hettinger says. If your tap cold water temperature falls below 60 degrees F, he recommends using a cool setting, which adds a small amount of hot water to the load, to help activate the laundry detergent.

For other ways to make laundry day more sustainable (and extend the life of your clothes), consider air-drying your clothes instead of popping them in the dryer. This decreases your laundry day energy use while reducing color fade and the appearance of wear. And if you're appliance shopping, consider a high-efficiency washer instead of a standard deep-fill machine.