Hardwood floors can be cleaned with ease when you catch a stain before it sets in. Getting rid of dark stains on hardwood floors may take a little more work to get the damage removed. First of all, most dark stains on hardwood floors are created when the liquid spilled on the floor has remained there for too long. Too long can be a few minutes or it can be days, depending on your flooring. It will also depend on what has been dropped or spilled. If you have spilled red wine on a natural hardwood floor, the stain may be more difficult to remove. Most hardwood floors have a finishing on the wood to protect it from stains and damage. An older floor or one that was not sealed after installation, such as the new tongue and groove ready to install flooring, can have a dark stain set in minutes.
To remove dark stains on hardwood floors you need to take it a step past just removing the stain with a cleaner. You will actually have to resurface that area of the floor. To start this process you will need a sander and new sealant. The sealant is usually urethane. If you have an old floor, you may wish to refinish the entire floor to remove all the stains. If you are doing the entire floor, you will be able to rent a commercial sander that will allow you to work with a little more ease. A smaller area may just require a little sand paper and muscle. When the area has been sanded you will want to use an oxalic acid crystals in water mixture. Follow the directions carefully. These crystals are extremely hazardous to skin so you will need to wear gloves. Soak a white cloth in the acid mixture and apply to the stain for about an hour. After an hour check the stained area to make sure it has been bleached away. It may take several applications. If after a couple of hours the stain is still not disappearing, you may have to consider other options. If the stain is removed, you will need to wash the floor with household vinegar to neutralize the acid. It will take a few hours to make sure the hardwood flooring is dry before you begin the next process.
If the stain is deep, you may have to replace that section of flooring. If it is not a deep stain, you should be able to save the floor. Depending on your next action, you will need to match the stain of the hardwood. It will take at least one coat of stain to create a seamless look to your floor. Once the stain is dry, you can use the sealant to protect the floor from any further stains. You will need to dispose of the acid properly when cleaning up from the job.
If you are concerned about how any cleaning solution will affect the look of your floor, test it on a small area or scrap piece of flooring first. It’s better to be sure of the outcome than to find out it’s not what you wanted.