How-to's Woodworking Ideas

How to Remove Dark Stains From Hardwood Floors

The sight of dark spots on an expensive hardwood floor is one every homeowner dreads. Indeed, it’s the main reason many homeowners seal their wooden floors with high-end finishes. A proper sealer protects the underlying surface and makes the floor more stain-resistant.

Unfortunately, a few dark spots are inevitable and can result from various factors, from spilled drinks to chemical cleaners and moisture damage.

So, we want to explain how to remove dark and white marks from hardwood floors so you don’t live in constant fear of spilling something on the floor.

What’s the Best way to Remove Black Stains From Hardwood Floors?

A white vinegar solution provides the best solution for removing dark stains from hardwood floors. Mix one part warm water with one part white vinegar and rub it on the affected area using a soft rag. It is a stain remover and a soft bleaching agent, thus easily removing dark spots.

What Causes Dark Spots on Hardwood Floors

Hardwood floors can exhibit dark spots for many reasons, including natural causes, spills, and poor cleaning products/methods. Nevertheless, you want to be particularly wary of the following;

  • A blotchy finish

Inconsistencies in hardwood floor finishes are one of the main causes of dark spots. For example, perhaps the wood doesn’t absorb color pigments evenly. Or, maybe you used an incompatible product. Poor surface prepping, lack of priming, and using the wrong primer can also cause darkening in some sections.

  • Sap stains

Sap stains occur for two reasons. First, the stains may occur naturally due to oxidizing enzymes in the sapwood. Alternatively, the discoloration may result from various fungi in the sapwood. Nevertheless, they cause dark brown or blue stains that are difficult to remove.

  • Iron stains

Iron stains, or rust stains, are iron oxide marks. They are essentially rust deposits that exclusively result from a reaction between water or moisture and iron metal. So, to trace the source of the rust, you need to ask where the iron minerals originated. For instance, did you buff the wood with steel wool? If so, then a water-based finish will certainly result in iron stains.

  • Sticker stains

Wood planks in the timber yard are separated using thin strips to encourage air circulation. This helps prevent warping, shrinking, and mold growth. Unfortunately, the thin strips, better known as stickers, may leave dark brown or blue stains on the wood planks that you cannot remove by sanding.

  • Chemical stains

Chemical stains are caused by spilling or using chemicals on wooden surfaces or items. For instance, milk spills will quickly discolor your hardwood floor because of the lactose, galactose, calcium, and potassium content. Acetone, acetic acid, and chlorine can also discolor wooden floors. Similarly, spilled wine, tea, or coffee may cause stains if you don’t wipe the surface immediately.

  • Moisture and water stains

While spilled water may not cause hardwood floor stains, prolonged ponding or damp conditions almost always result in dark spots. The same applies to extended exposure to moisture. This is because the water eventually penetrates the surface from micropores on the surface, causing mold and rotting.

  • Other causes

Other causes of black spots on hardwood surfaces include blood droplets, pet mess (such as pet urine), and ink stains.

Black Stains on Wood Floors: Prevention Tips

Before we discuss how to remove dark stains from hardwood flooring, perhaps we should begin with prevention tips. That way, you don’t have to remove any spots in the first place.

  • Protect your floors

Waxing is one of the most effective ways to protect your wooden floors from dark and white marks. You can also use a different sealant, depending on the wood type. Consult a professional for your best options.

  • Wipe spills immediately

Don’t let water, beverage, or other spills sit on the floor for more than a few seconds. Instead, clean it up with a dry rag right away, then wipe the spot with a solution of one part water and one part white vinegar.

  • Regularly clean the floor 

Mounds of dust and dirt invite pests that may bore holes into the floor. Moreover, the dust heaps eventually absorb moisture (even in dry climates), which can cause mold growth and rot.

  • Watch your pets and indoor plants

Keep your pets clean and dry and clean after them promptly. You may also want to train them not to urinate or poop everywhere. Similarly, check on your plants. Do they drip water? Does the pot leak?

  • Control indoor humidity

High humidity levels in the house cause condensation on the walls, ceiling, and floor. The dripping or pooling water can cause black stains. Moreover, damp conditions can attract white mold stains.

How to Remove Black Stains From Hardwood Floor

Unfortunately, sometimes black marks and white stains appear from “nowhere” even if you take every preventive measure. Don’t fret. You can easily remove most hardwood floor discolorations with basic tools and supplies. Here’s how;

Supplies for removing black stains from hardwood floors

  • Cleaning agent
  • Sandpaper
  • Fine steel wool
  • Dry cloth(s) and microfiber cloth
  • Wood stain
  • Wax topcoat + applicator brush/roller

How to Remove Black Stains on a Wood Floor: Step-by-Step Guide

Begin by wearing protective equipment. For instance, wear protective gloves to protect your hands and goggles to protect your eyes. You may also want to wear a mask when using strong stain removers.

With that done, proceed as follows;

Clean the surface

You want to spot clean the affected area as you don’t want to work on a dusty surface. Moreover, the stain-removing solution may not work effectively on a dirty surface.

So, bring out your vacuum cleaner and run it over the section. You can also sweep it. When you’re done, prepare a liquid dish detergent solution (detergent + cold water), dab a cloth in the solution, and place the damp cloth over the affected area. The intention is to soak the stain to saturate it.

Allow it to soak for five minutes. Then gently scrub over the area with a damp cloth. Don’t be surprised if some of the debris comes off. For instance, urine stains easily come off from hardwood floors after a gentle wash with a detergent.

If the stain is still visible, soak soft steel wool in a mineral spirit and go over the surface again. Mineral spirit is a solvent that removes sealers, stains, and wax. Next, rub the steel wool gently in small circular movements. Then let the wood dry for 12-24 hours. You’ll find most of the stains done.

Sand it with fine-grit sandpaper

If you can still see the stains, it’s time to up the tempo with a thorough sanding. A proper sanding removes stains stuck on the wood surface as long as they’re not deeply ingrained. For instance, it removes wood stain, wax, and sealant.

We recommend handheld sandpaper. Start with 120-grit sandpaper and aggressively rub it over the surface. Then wipe the dust with a dry cloth to see if the mark is gone. If not, pick softer sandpaper, such as 150 grit, and continue rubbing.

Go all the way until 220-grit sandpaper, wiping the surface regularly with a dry cloth to assess your progress.

Apply a stain remover or removal solution

Most wood stains are usually gone after a thorough sanding. But, unfortunately, some stubborn stains won’t leave until you engage the final gear – stain removers.

The good news is that many people have tough hardwood floor stain removers on hand. So, you don’t need to visit the store. The following are a few products you can use for stain removal on hardwood floors.

How to remove dark stains from hardwood floors using hydrogen peroxide

Hydrogen peroxide is a powerful all-purpose cleaning formula found in many homes. It combats dirt, debris, and stains alike. Moreover, it’s safe for kids and pets as long as you don’t leave the bottle open.

Another reason we like it is it doesn’t damage wood surfaces. Also, you can use it out of the bottle – no need to dilute or mix it with anything.

  1. Grab a dry cloth and soak it in hydrogen peroxide.
  2. Dab the damp cloth on the affected surface.
  3. Allow the damp cloth to stay over the stain overnight.
  4. Remove the damp cloth and check whether the stain is gone.
  5. Repeat steps #1-4 until the stain disappears

How to remove dark stains from wood floors with baking soda

Baking soda is another solution you can use to remove stains from wood surfaces. It works like hydrogen peroxide, removing tough stains, eliminating odors, and cleaning difficult areas. It’s also more readily available in many households than hydrogen peroxide.

The main difference is that you need to mix the powder with water to form a cleaning paste. Here’s how to use it to remove wood stains;

  1. Wear gloves to protect your hands
  2. Make a paste of three parts baking soda and one part water.
  3. Apply the paste over the affected surface
  4. Let the paste sit over the area for at least an hour.
  5. Clean the spot with a soft, dry cloth
  6. Repeat steps #1-5 until the stains disappear.

How to get dark stains out of hardwood floors with white vinegar

Alternatively, you may only have vinegar in the house. It works the same way as hydrogen peroxide and baking soda, breaking down hard stains to remove them from surfaces. Moreover, it is completely safe for your kids and pets. Also, vinegar removes odors, leaving your home clean and fresh.

However, you must first dilute the solution as concentrated vinegar can bleach wood surfaces. Here’s what to do;

  1. Mix one part white vinegar with one part water.
  2. Soak a clean cloth in the solution and dab it over the stained area.
  3. Let the stain soak up the vinegar for at least an hour.
  4. Apply a little pressure as you gently rub over the stain.
  5. Assess your progress and repeat if necessary until the stain is gone.

How to get black marks out of hardwood floor with a stain remover

Finally, for extra-tough stains, consider getting a factory-made stain remover. The products come in many forms, so you must be keen. We advise getting a specialized remover for that stain.

For instance, some removers are specifically made to tackle pet messes. Meanwhile, others target mold and mildew spots while others remove beverage spills. First, identify the stain, then find a matching remover. After that, follow the application guidelines on the product label.

Generally, you need to do the following;

  1. Apply the stain remover as directed (you can spray it or apply with a dry cloth, etc.)
  2. Wait a few minutes for the remover to work its magic (this can take a few minutes to a few hours).
  3. Wipe the surface with a damp cloth to remove the residue
  4. Allow the floor to dry.

Stain the section

After removing the stain, it’s time to restore the floor. Begin by purchasing a sealer. Of course, you need one that matches the old sealer. So, check if you have some left in store. Alternatively, bring the can to the hardware store or take pictures to refresh the attendant’s memory.

Once you have the paint, get down to work;

  1. Sand the area lightly
  2. Use a dry cloth to wipe off the sand dust.
  3. Use a new dry cloth to rub the sealer over the affected area.
  4. Remove the excess stain with another dry cloth.
  5. Allow the surface to dry overnight or as the manufacturer directs.
  6. Apply the second coat
  7. Let the area dry completely for 24-48 hours.

Apply wax or wood varnish

Finally, you’re almost done. After resealing the floor, you must wax it to protect the underlying surface from weather elements, spills, and dirt.

Alternatively, you can use a finishing sealant or polyurethane. Our advice is to use the same wisdom as above – find out the top coat used in the rest of the floor and get the same product. This ensures consistency and surface uniformity.

Apply the finish as directed by the manufacturer. Many products are best applied using a brush or microfiber roller. The manufacturer will indicate the number of coats needed to achieve the perfect finish. However, two coats are standard. Allow the first coat to cure fully (it often takes 24 hours) before recoating.

How to Choose the Right Cleaning Method for Various Hardwood Floor Stains

As you’d expect, a single cleaning method may not remove all types of hardwood floor stains. So, here’s how to pick the right removal method for common stains.

  • Moisture and water stains: We recommend liquid detergent for light-moisture and dark water stains. However, consider hydrogen peroxide and oxalic acid for aged water and condensation marks.
  • Mold and mildew: Baking soda is the best solution for removing black and white mold spots. The main reason is that baking soda has antimicrobial properties. Additionally, it removes mold odors.
  • Dirt and ink stains: White vinegar and hydrogen peroxide are the best choices for removing dirt and ink stains. Alternatively, consider a store-sourced cleaner, such as Goof-Off.
  • Vomit, urine, and feces: The best solutions for removing potty messes are baking soda, white vinegar, and hydrogen peroxide. All three disinfect the surface. Additionally, they remove strong odors.
  • Blood, wine, and other deep stains: Blood, wine, and deep stains can be difficult to remove. So, consider chlorine bleach or oxalic acid. It helps to clean the mess quickly before it seeps too deep.

When to Call a Professional

Unfortunately, some hardwood stains won’t come off completely no matter the stain removal method. Alternatively, you may discover that the stain was etched into the wood by a sharp object or through wear and tear. These are a few cases when you should consider professional assistance.

We also recommend calling a professional when dealing with a high-end floor, such as Mascara ebony floors, which cost $150+ per square foot.

When to Replace Stained Wood Floors

Replacement is rarely necessary when dealing with black spots on hardwood floors, as strong stain removers almost always eliminate the mess.

Unfortunately, sometimes nothing seems to work. Moreover, perhaps you’re dealing with a large area spanning several square feet. In that case, you need to consider more drastic solutions, including replacement.

However, before you think about replacement, speak to a wood flooring specialist about refinishing. A thorough sanding and new coat of finish will almost certainly overpower the dark stain. Only replace the stained wood panels or the wood floor if the specialist so advises.

The Best Hardwood Floor Stain Remover

If you choose to use a hardwood floor stain remover, the next step is to find the right one. The following are three top-rated hardwood floor removers to consider;

  1. Bissel Professional Stain and Odor

Bissel Professional Stain and Odor is a formula specially designed to remove stains, including makeup, pet soils, spaghetti, motor oil, french fry oil, and blood from hardwood surfaces. In addition, it uses patented technology to remove tough odors, including smoke, mold, and mildew.

The best part is it contains no heavy metals, dyes, phosphates, or optical brighteners, thus doesn’t affect the underlying floor surface. Instead, it uses selected enzymes to break down and eliminate stubborn stains and odors.

  1. Simple Solution Hard Floor Pet Stain and Odor Remover

Another product to consider is the Hard Floor Pet Stain and Odor Remover by Simple Solutions. It removes pet urine, feces, and other common messes on sealed hardwood floors and other surfaces such as vinyl, brick, and concrete.

The product features a special 3-in-1 nozzle sprayer for greater versatility, allowing you to steam, foam, or mist the affected area, depending on the type of mess. Moreover, it penetrates the wood surface without damaging the wood itself.

  1. Goof-Off Household Heavy Duty Marks, Messes, and Stain Remover

This product from Goof-Off is also very effective in removing common hardwood floor messes. Specifically, it targets mistakes ordinary cleaners can remove, such as ink, marker, lipstick, and scuff marks. It also removes mold spots and shoe polish.

Apply the formula directly to the stained area and let it settle for one to five minutes. Then wipe off with an absorbent cloth. It removes stains the first time by cutting through the mess.

FAQs

What does it mean if wood floors turn black?

A black hardwood floor is often a sign of mold caused by excess moisture/humidity. This is especially true if the black stain is in an area prone to spills, flooding, and urine messes. Black mold (and mildew) thrives in such areas.

How do you get black stains out of wood?

An easy way to rid wooden surfaces of black stains is to cover the affected area with paper towels dipped in a vinegar solution. Allow the surface to soak up the vinegar solution for 30 minutes. Then wipe it with a clean damp cloth and allow it to dry for another 30 minutes.

How can you get black stains out of hardwood floors without sanding?

There are several ways to remove black stains from wood floors without sanding. For instance, a hydrogen peroxide or vinegar solution will do the job easily. Wet a few paper towels with the solution and dab over the affected spot for 30 minutes. Then wipe with a damp rag.

What’s the best stain remover for wood?

The best wood stain remover is DEFY Exterior Wood Stain Stripper. It’s a water-based stain stripper that eliminates all types of hardwood stains, restoring the natural wood beauty. Deck Wood stain stripper, Criststrip Paint Varnish Stripping Gel, and Sunnyside 2-Minute Advanced Paint Varnish Remover are other good options.

How can you fix a discolored wood floor?

It’s not too difficult to fix a discolored wood floor, especially darkened sections. Two solutions to consider are oxalic acid and two-part peroxide bleach. These two lighten darkened wood and are easy to use. Mix the chosen product with water to form a solution and apply the solution over the darkened wood section.

Summary

Removing stains from wooden floors shouldn’t be too big a challenge. Indeed, sometimes a gentle wipe with a damp cloth is enough to remove the dark spots. However, consider hydrogen peroxide, white vinegar, baking soda, or a factory-made hardwood stain remover for tougher stains. Good luck!