Has the carpet in your apartment ever turned yellow after cleaning?
If it happens, you wouldn’t want to leave the carpet in that state – you’d want to restore its color. But first, you need to know the different types of carpet yellowing and how to handle them.
Carpet can turn yellow from normal stains, chemical stains, or phenolic yellowing.
If you found yellow streaks on your rug after cleaning, there’s no need to fret. You can remove the stain using an acid rinse, extraction cleaning, isopropyl alcohol, vinegar, and citric acid, among other methods.
Some chemical carpet yellowing, on the other hand, cannot be removed. You’ll have to either dye your rug or replace it with a new one.
Let’s look at the types of carpet yellowing, causes of carpet discoloration, and how to restore your carpet in detail.
What is Carpet Yellowing?
Carpet yellowing is the discoloration of carpets with yellow stains or spots.
It can occur from substances staining the carpet fibers or a pre-existing chemical used to manufacture the rug. Sometimes, yellow streaks can appear on your carpet after you’ve cleaned it.
Types of Carpet Yellowing
Normal carpet yellowing
Normal carpet yellowing occurs when everyday substances stain your carpet. Pet urine discolors the rug, while tar stains leave a yellow cast. Wicking can also cause normal carpet yellowing after cleaning.
Moreover, the parts of your carpet exposed to traffic accumulate dirt and other residues. After a while, it changes color and can become yellow. This causes a disparity between the color of the preserved part and that of the exposed part.
Certain procedures can fix normal carpet yellow stains and restore the rug to its original color.
Chemical yellowing occurs when chemicals change the composition of the fibers. Chemical substances like high-ph or alkaline detergents and baking soda can leave a stain on your carpet after cleaning.
Most chemical carpet yellowing can be fixed by applying an acid-based solution.
Phenolic yellowing is a type of chemical yellowing. It occurs in carpets that have butylated hydroxytoluene (BHT).
Carpets with BHT require enough breathing space. When objects like furniture are placed on it, the covered area does not receive enough air. The BHT reacts and causes carpet yellowing.
Reversing the effects of phenolic yellowing on your carpet can be challenging. Exposing the rug to air can lead to a gradual restoration of its color. Citric acid can also be used to treat phenolic yellowing. However, there’s no guarantee that these processes will work.
In some cases, you might have to dye the carpet or replace it.
Causes of Carpet Yellowing
Carpets can turn yellow due to several reasons. Here are some of them:
Sometimes, stains on your carpet are deep. They might have gotten into the carpet padding or moved to the subflooring.
When you clean a yellow stain off your rug, you’re only cleaning the top. After a few days, the dirt in the underlying pad will have traveled up the carpet fibers, and the stain will reappear on the same spot.
Wicking can also occur when you steam clean your carpet. Because the rug is wet after cleaning, dirt that was trapped in the underlying pad can move up the carpet fibers and appear on the surface.
After washing your carpet with baking soda and drying it, the carpet’s original color should be restored. But this does not always happen. You may find out that baking soda has made your carpet yellow.
To restore the color of your carpet, use white vinegar mixed with water. Every time you use baking soda to clean, you can also apply a vinegar solution after cleaning with the baking soda. This process will ensure you don’t have a discolored carpet.
The effect of photo-oxidation occurs when the carpet is exposed to sunlight, regular light, or atmospheric fumes. Photo-oxidation can cause the degradation and discoloration of rugs with wool, silk, and polypropylene fibers.
Most carpets have a higher quantity of yellow dye. Once you expose the fibers to sunlight, the other colors fade out and leave behind a yellow tint.
Fluorescent brightening agents
Fluorescent brightening agents turn yellow when exposed to ultraviolet light. Although carpet manufacturers do not approve these agents, you’ll find them in some cleaning products.
The moment you apply such cleaning products to your carpet, the result will most likely be yellowing.
Your best bet is to study the label of any cleaning product you buy and make sure it doesn’t have any fluorescent brightening agent. That way, you can avoid the hassle of trying to restore the color of your carpet.
Alkaline cleaners that have a ph level of 10 or more can discolor your carpet. This usually occurs in carpets with wool or nylon fibers.
You can do an acid rinse or use a neutralizer to restore the original color of your carpet. Better still, you can use a cleaning product with a lower ph level.
Butylated Hydroxytoluene (BHT)
Butylated hydroxytoluene is a preservative used in plywood, plastics, and various items. BHT is an antioxidant and ultraviolet inhibitor that was used in the production of latex and carpet adhesives. It is also sometimes used in carpet pads or cushions to increase the lifespan of the carpeting.
BHT is the key ingredient in phenolic yellowing.
Because natural carpet padding can be prone to mold, most of them are made with synthetic material. With carpet cushions that have BHT, the fibers are exposed to the gas for a long period.
When you install a new carpet, the fibers would need to release the chemical remnants of the gas into the atmosphere at low levels. It might last up to several weeks before BHT finally dissipates.
If you immediately place your furniture on the carpet after installation, it covers and seals in that area. There won’t be aeration, and the gas won’t be expelled from the fibers. A chemical stagnation occurs, leading to a yellow discoloration of the carpet.
You can reverse phenolic yellowing in its early stages by exposing the affected area to air.
Aside from BHT, other special finishes can lead to carpet yellowing. Antistatic agents, crease-resistant finish, softeners, and flameproofing agents that are used for rugs and furniture can result in carpet discoloration.
Silicone is a polymer. Polymers degrade and oxidize when exposed to heat, light, and chemicals. As the silicone protector is exposed to all these elements, oxidation occurs, and it turns yellow.
Carpet yellowing is especially rampant in stain-resistant nylon carpets with silicone protectors.
Loom oil or mill oil is a lubricant used in tufting machines. During tufting, the loom oil sometimes gets spilled on the carpet. This spill can result in yellowing of the affected area.
The discoloration usually appears in straight lines and becomes darker as the area gets walked upon or exposed with time.
Spills from sugary drinks, can also cause carpet discoloration if they’re left unattended for an extended period.
When asphalt driveways have just been sealed or repaved, footwear can pick up asphalt residue. The asphalt coating is then rubbed off on the carpet inside, which then causes the carpet to turn yellow.
This affects rugs placed near the entry areas in the house the most. It also commonly occurs during periods of high temperatures, like summer.
There are household products that can cause carpet discoloration when they come in contact with the fibers. Examples of such products are insecticides, household bleaches, fertilizers, furniture polish, and some plant foods.
Besides, some of these products contain benzoyl peroxide. As a result of the benzoyl peroxide, a dark yellow or orange stain spot can appear on your carpet. The stain lightens in color with time. Sometimes, the spot appears as a yellow stain with an orange ring around it. In blue carpets, the stain can be pink or whitish.
Smoking can lead to permanent yellow streaks and stains on carpets, if not treated almost immediately. Getting rid of stains caused by nicotine is very difficult.
The only way to ensure your carpet isn’t stained with nicotine is by regularly cleaning your carpet. For effective results, use the services of a professional cleaner. You can also use a carpet cleaning machine to get the job done.
Most times, residues are left behind after cleaning your carpet. These residues could be from the shampoo, soap, or carpet cleaning product you used.
Because the residue is sticky, it attracts dust and dirt from shoes. This dirt ends up discoloring the carpet. Stains caused by these residues might take days or weeks to form.
How to Handle Carpet Yellowing
There are different types of carpet discoloration. Some types can be removed, while others have no remedy and can only be prevented. If your carpet has turned yellow, here’s what you need to do:
How to Handle Normal Carpet Yellowing
Professional cleaning of your carpet can get rid of yellowing caused by wicking. During the cleaning, the stained areas will be treated, and the original color restored. This helps every aspect of your rug to have matching colors.
Extraction cleaning will not only remove the stain at the top of the carpet, but the steam will also extract the dirt inside the fibers and in the underlay. As a result, you won’t have to worry about future yellowing.
Tar oil stains
Tar oil stains can leave a yellow cast on your carpet.
When you discover tar on your carpet, you can remove the stain using the following method:
- Scoop up the tar.
- Blot the area with a towel.
- Vacuum the area.
- Apply a carpet cleaning solution or dishwashing liquid to the stain. Start from the outer part of the stain and move inward. This will ensure the tar stain doesn’t spread.
- Rinse the area with cold water.
- Repeat steps 1-5 until the stain has been removed.
- Dry the carpet with a hand dryer or place a clean white towel on the affected area and leave overnight.
- Vacuum the spot again to ensure there is no tar residue left.
If the cleaning solution did not remove the stain, pour rubbing alcohol or 3% hydrogen peroxide on the spot. Leave for a few minutes. Then, blot it with a paper towel. Repeat the drying process.
Pet urine can result in carpet yellowing. To get rid of this mess, use the following instructions:
- Blot the affected area with a white piece of cloth – this absorbs the wetness.
- Wet another white cloth with isopropyl alcohol.
- To ensure effectiveness, test the alcohol on the part of the carpet that is not visible.
- After that, you can apply it to the stain.
Other yellow spots
Unidentified yellow spots on carpets with synthetic or woolen fiber can be removed using lemon juice and salt. The process is simple:
- Pour a mixture of lemon juice and salt on the spot.
- Rinse with water.
- Use a white towel to dry the area.
How to Handle Chemical Carpet Yellowing
Sometimes, alkaline cleaning products can make carpets turn yellow. One way to fix alkaline-induced yellowing is with an acid rinse.
An acid rinse involves using an acid-based product to rinse out the cleaning product. The acid rinse will not only rinse out detergent residue but will also neutralize the alkaline and stabilize the dye used for the carpet.
Avoid high-PH detergents
Acid rinse is a correction method for chemical yellowing. You can, however, avoid your carpet yellowing by using detergents that have less alkaline, are neutral, or are acidic.
Using baking soda to clean your carpet can cause yellowing. If you notice discoloration on your carpet after using baking soda to clean, here’s what you should do:
- Mix water and white vinegar in a bowl. Some people recommend using one part water and one part vinegar. Others recommend using three parts water and one part vinegar. You can start with the latter to be safe.
- Use a sponge to apply the solution to the baking soda stain.
- Apply pressure to the area with a white towel or cloth. Repeat the process a few times till the stain disappears.
- Let the carpet dry naturally.
Alternatively, you can use this method:
- Pour a mixture of vinegar and water into a spray can.
- Spray the affected area with the solution.
- If there’s dirt in the fibers, use a carpet washer to clean it and let it dry.
- Repeat the process until your rug’s color is restored.
How to Handle Phenolic Yellowing
If your carpet has experienced phenolic yellowing, there are a few ways you can deal with it:
Phenolic yellowing in carpet is caused by butylated hydroxytoluene (BHT). It is usually bright yellow or legal-pad yellow.
To remove phenolic yellowing, you can create a citric acid solution — here’s how:
- Mix 8 to 10 tablespoons of citric acid with 1 gallon of hot water.
- Pour the solution into a spray can and apply it to the affected area.
- Dry with a hand dryer or white towel.
- Vacuum several times to remove the citric acid residue.
If the phenolic yellowing is freshly occurring in covered areas, giving the affected area enough room to allow air will reverse it.
To enable this, remove furniture and anything covering the carpet. As the BHT is exposed to air, the yellowing will gradually disappear. Once your carpet’s original color has been restored, air the covered areas from time to time to avoid reoccurrence.
Dyeing the carpet
Sometimes, phenolic yellowing won’t go away even after you’ve aired it or used citric acid. This permanent discoloration occurs because the composition of the carpet fibers has been changed.
At other times, photo-oxidation occurs, and your carpet is left with a yellow blotch.
At this point, you can dye the carpet if it has nylon or woolen fibers.
Note that you can’t dye a carpet to a lighter color. You can only dye to match its color to a darker color.
Replace the carpet
After every color restoration procedure has failed, another option is to pull out your carpet and install a new one.
As problematic as carpet yellowing can be, it can be fixed by using the right procedures most times.
Various factors can cause a yellow discoloration of your carpet. This can be annoying and embarrassing, especially when you have a light-colored carpet because the stain will be more visible.
While you can remove some of these stains with store-bought products, others require professional services.
Other forms of carpet discoloration, especially phenolic yellowing, cannot always be reversed. The only way to get rid of such stain is by dyeing the carpet to match its original color or replacing it with a new rug.
Carpet yellowing is very common, but handling and removing such stains shouldn’t be so difficult. All you need is to know the underlying cause and the appropriate procedure required to restore the carpet to its original color.