We get one question more than any other—How can my laundry get clean with so little water? Some people are so concerned when they look into the machine, they tell us that they add buckets of water to the washer.
While it's true that to increase efficiency, modern washers are engineered to use as little water as possible, you don't need to add more water. In fact, modern washing machines will drain any excess water, so there's no advantage to adding more.
We did some tests in our laundry labs to compare the cleanliness of clothes washed with more water to clothes washed with the machine's usual amount of water. We did the laundry in a newer top-load machine, the GE GTW685BSLWS. And our testing showed that adding more water to a wash load actually gives you dirtier clothes.
What we did
To test for cleaning power at different water levels, we started with stain strips. These are stained with some of the toughest laundry challenges—blood, red wine, sebum, cocoa, and carbon (to approximate soot and oil stains). We stained some additional fabric using coffee grounds to mimic dirt, and a solution of bright purple dye.
We washed the our stained fabrics on separate cycles, using the same amount of detergent for each on the washer's Colors setting. But on one cycle, we added 46% more water.
When we compared the two loads, we saw these results:
• The purple dye washed away completely in both cases.
• Running each load left coffee grounds on the fabric.
• Using the standard amount of water in the Colors cycle got the stain strips about 4% cleaner than the strips we ran in the cycle with extra water.
Using additional water does not get your laundry any cleaner. Why? Because the extra water dilutes the concentration of detergent, and reduces the mechanical action of the clothes rubbing against one other, the tub, or the agitator, which helps remove dirt and stains.
If your clothes aren’t getting clean enough for you, don’t add more water. There are other strategies you can implement to get your laundry sparkling clean.
• Don’t overload your washer with clothes. Your laundry needs room to move around.
• Try using the Heavy cycle on your washing machine.
• Use a better laundry detergent. When we tested liquid laundry detergents, Persil ProClean rated Best Overall, removing 2% more stains than Tide HE Turbo Clean, which we rated Best Value.
• Use less detergent, not more. Too much detergent can make your clothes feel soapy and greasy, and it can leave behind white spots. Filling the cup more than a third full is a mistake. A couple of tablespoons of liquid laundry detergent will work in many cases.
• Shake loose dirt out of clothes before you put them in the washer.
• Pretreat stains with cold water or stain remover before you wash.