How to Remove Old Urine Stains from a Carpet

Pet urine stains can cause permanent damage to a carpet. The longer the dog urine stays on the carpet, the more it gets down deep into the fibers, causing a yellow stain and nasty odor that won't go away. Although it's best to deal with the stain immediately, sometimes circumstance prevent this from happening. Fortunately, there are some methods you can try to remove old pet urine stains on the carpet.

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How to Remove Old Urine Stains from a Carpet

When There are Urine Stains on the Carpet

Dog urine is highly acidic. A fresh stain shouldn't cause much damage if it's taken care of immediately after the accident occurs. Once the stain dries, the ph level in the acid rises, causing ideal conditions for bacteria to flourish. Not only does the bacteria cause the acid to oxidize and stain the carpet, but the bacteria and organic matter in the urine also cause an unpleasant odor. The longer the stain languishes, the worse the odor gets and the harder the stain is to remove.

How to Clean Urine Stains on Carpet

Fresh urine stains on the carpet aren't too difficult to deal with. The trick is to get all the liquid out of the carpet before wicking occurs, and the dog pee travels down the carpet fibers and pools at the bottom.

Fold a dry cloth or towel and press it firmly over the stain so it absorbs as much urine as possible. After extracting as much liquid as possible, sprinkle baking soda on the stain and leave for at least 30 minutes to absorb any remaining urine and neutralize odors. Vacuum the baking soda afterward to remove it from the carpet.

A solution of 1 part dishwashing liquid to 1 part water can help to clean dog pee on the carpet. Use a sponge to blot the solution on to the stain. Avoid pouring the solution on the stain as that will just cause more liquid to sit at the bottom of the carpet and could stain the floor underneath. Continue to blot the stain until it's gone. When there's no more urine, blot with a clean damp towel to "rinse," then a dry towel to remove excess moisture.

For lingering stains or stains that are a day or two old, use a towel and baking soda to soak up any moisture and blot with a solution of one part vinegar to two parts water. Avoid using vinegar on fresh pet stains as the acid in the vinegar can react to the acid in the urine.

Avoid cleaning pet urine stains with acidic cleaners or those that have a high ph factor. Don't use a steam cleaner or apply heat to a pet stain as that will cause it to set in and become permanent.

How to Clean Old Dog Urine from the Carpet

If the pet stain doesn't come out with vinegar or soap, or if the stain is old and set into the carpet, pet enzymes can help. The enzymes cut through the bacteria to remove both stain and odor. Professional carpet cleaners sell pet enzymes, and they can also be found in stores that sell pet or heavy duty cleaning products.

Spray the enzyme-based cleaner directly onto the stain and follow the directions on the label for waiting time and removal. If the stain won't come out, contact a professional carpet cleaner.