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Choosing & Understanding the Best Paint Strippers

how to safely remove paint from wood

When attempting to remove paint from an exterior wall or surface, it may be tempting to use aggressive methods such as power washing, sandblasting, or wire brushing. However, these techniques can come at a high cost as they pose a significant risk of damaging your brickwork and other surfaces, leaving them vulnerable to the elements. In addition, the damage caused to your brickwork and exterior walls can not only be expensive to repair but also result in dampness within your building structure. To avoid such complications, we offer tips on the best practices for removing paint from brick and wood, along with information on the different types of paint strippers designed for this task.

Types of Paint Strippers

Solvent-Based Paint Strippers

bubbling of solvent based paint strippers

Paint can be removed from a surface by utilising solvent-based strippers, which dissolve or soften the bond between the coating and the substrate, resulting in the paint bubbling up. The most commonly used solvent for this purpose is methylene chloride, but other solvents such as alcohol, toluene, acetone, and ketones are often incorporated as well.

Despite their effectiveness, methylene chloride-based strippers pose significant health risks, as they can temporarily reduce the blood’s oxygen-carrying capacity, cause permanent damage to the liver and kidneys, and potentially lead to cancer. As a result, the European Union banned the use of methylene chloride in paint strippers intended for consumer use in 2010, restricting its usage to workshops exclusively, and proof of such will be required before purchase.
N-methyl-2-pyrrolidone (NMP) is another solvent frequently used with dibasic esters (DBE) as a safer substitute for methylene chloride. However, the full range of their health effects remains uncertain. The EPA has identified NMP as causing skin swelling, irritation, and blisters. DBEs cling well to vertical surfaces, but they work slowly and can leave a fuzzy surface on the wood.
Another solvent combination consists of alcohol, toluene, and methanol, which works rapidly but is highly flammable and evaporates quickly. Breathing this mixture can lead to brain damage. However, this mixture’s quick evaporation somewhat reduces the waste volume that must be disposed of.

Caustic-Based Paint Strippers

Caustic strippers are water-based with a pH range of 13 to 14 and contain lye as their active ingredient, which can be either potassium hydroxide or sodium hydroxide. In these types of strippers, the lye reacts with the oily component of the paint film, transforming it into soap and loosening it from the surface.

However, caustic strippers also pose health risks such as skin burns and lung irritation. In addition, caustic-based paint strippers can also lead to issues relating to dampness. Caustic alkalis can also harm the cellulosic fibres of wood, resulting in irreversible damage. Finally, it’s worth noting that hardwoods should never be stripped with caustic paint removers, as this can cause the wood to turn black.
caustic based solvents paint strippers

Health and Safety

goggles and full face mask paint stripping protective gear

It is essential to be mindful of basic health and safety precautions when using any paint stripper, as these products contain chemicals that can pose inherent risks. Here are some important considerations to bear in mind while handling them:

  1. Always read the labels and technical and safety data sheets. Each paint comes with its description but also its risks. Do not gamble with your health and safety.
  2. Inhalation of these chemical fumes can be detrimental to your health. When working indoors, always work in well-ventilated areas and wear breathing apparatus where appropriate.
  3. Take care to avoid skin contact. Paint strippers can irritate your skin and can occasionally cause more than just a rash. Wear suitable gloves and other protective clothing.
  4. Protect your eyes and ensure no paint stripper gets into them, as it can cause severe damage.
  5. Do note that the more complex formulations are not flammable.
  6. Wear a respirator designed to exclude solvent vapours, and make sure that they supply filtered compressed air from your compressor—Don safety glasses and neoprene or butyl gloves. 
  7. If you must work indoors, stay within the 25 ppm exposure limit for methylene chloride.
  8. The air in the room must change 7-10 times an hour. To accomplish this, arrange a fan behind you, so the air carries the vapours away from you and out a window, not toward you.
  9. Generally, paint strippers are highly flammable, so keep them away from open flames. 
  10. Finally, if you’re using a flammable stripper, make sure the pilot lights of nearby gas appliances are out.

Matching the Paint Stripper to the Job

Methylene chloride and caustic strippers effectively remove alkyd and latex paints. However, methylene chloride is slightly better at removing epoxies and polyurethanes. On the other hand, caustic strippers are more effective than solvents on alkyds, but they can darken wood and damage aluminium. Caustics also need to remain on the surface for longer, so they might not be the best choice for every job. Be mindful of the temperature, too; caustic strippers won’t work well below 10°C. And, of course, proper ventilation is crucial, especially if you’re working with methylene chloride.

matching paint strippers to the job
Some paint strippers are designed for specific applications. For example, if you’re working with milk paint, you can use a caustic stripper intended specifically for that purpose. On the other hand, if you’re dealing with lead-based paint, look for a stripper that contains lime, which will bond with the lead to prevent it from leaching into the waste.


DECAPANT is a powerful industrial-strength stripper free of CMR compounds. Powerful product designed for stripping particularly resistant industrial paints. 
DECAPANT is specially formulated for stripping paint from vats, floors and tools in paint factories.

Paint Stripping Tips

Methods and Equipment Considerations

paint stripping equipment and tools information

Strippers can be applied using various methods such as brush, roller, hand spray bottle, or sprayer, depending on the product consistency and area to be covered. However, it’s important to note that both solvent-based and caustic-based strippers can damage the rubber, leather, and aluminium parts of a sprayer. In such cases, sprayers can be fitted with neoprene or polyethene replacements for rubber components and stainless steel replacements for aluminium.

When using a caustic stripper, apply it thickly in one direction without brushing over the surface once it’s applied. This will create an airtight layer that helps keep the chemical moist and efficient. On the other hand, solvent strippers, whether liquid or gel, don’t require a thick application.

Removing Paint Stripping Residue

Once the stripper has been applied, it’s essential to leave the area completely and refer to your test patches to determine the appropriate wait time. When removing the residue, use a flexible-bladed drywall knife to scrape it into a plastic bag or paint container. Remember to dull the knife’s edge and round off the corners with a file to minimise the risk of gouging the surface. Unlike steel wool, a plastic scrubber is an effective tool to remove the remaining residue from wood pores without leaving behind rusty fibres.

how to properly disspose of paint stripping residue
To reach the nooks and crannies of the surface, use toothpicks, bits of paper, or similar tools. If paint remains after the first application, give it another stripping round. Always test the surface’s pH level with pH paper to ensure it’s reached pH 7. Solvent strippers can be washed off with mineral spirits, while manufacturers of methylene chloride-based strippers claim they clean up with water. However, using mineral spirits is the best option for stripping woodwork to avoid surface fuzziness caused by water.

Considerations for Porous Substrates and Caustic Strippers

wood vs concrete stripping paint

When using caustic strippers on porous substrates like wood or concrete, it’s essential to bear in mind that these materials will absorb alkaline material from the stripper. Despite neutralising the surface, the absorbed material can still bleed to the surface over time. To prevent any potential bleeding of absorbed alkaline material, it is advisable to neutralise the surface to pH 7, allowing for a few days of rest, and then double-check the pH before proceeding with painting. This precaution can ensure that the surface is completely neutralised and ready for a new coat of paint.

Proper Drying and Moisture Control Before Painting

To ensure a successful paint job after using a stripper, it’s crucial to dry the surface thoroughly before proceeding with further preparation and painting. Depending on the climate, this can take up to a week or more, so it’s important to be patient. Investing in a moisture metre can be helpful in determining the exact moisture content of the surface. For example, a surface with 15 per cent water content is too wet to paint, while 12 per cent is considered ideal. It’s worth noting that woods like cedar, cypress, and redwood contain water-soluble material that can bleed through the paint if the surface is damp. In such cases, it may take 60-90 days for the wood to dry completely.

Drying and Control Before Painting

Proper Disposal of Paint Stripping Waste

Paint-stripping waste typically contains chemicals and substances that can be hazardous to the environment and human health, so it’s important to dispose of it properly. Here are some general guidelines for disposing of paint-stripping waste:

  1. Check with your local authorities: Due to the varying environmental regulations in different locations, it is advisable to contact your local authorities or waste management department to determine the proper method of disposing of the residue generated during the stripping process.
  2. Use a designated hazardous waste disposal facility: Most communities have a designated hazardous waste disposal facility that accepts paint-stripping waste. These facilities are equipped to handle hazardous materials safely.
  3. Label and package the waste properly: When disposing of paint-stripping waste, make sure to label the container clearly as “hazardous waste” and package it properly to prevent leaks or spills. Use a container made of materials that can safely contain the chemicals in the paint-stripping waste.
  4. Do not pour the waste down the drain: Never pour paint stripping waste down the drain, as it can contaminate water supplies and harm aquatic life.
  5. Do not mix waste: Avoid putting stripping waste in a metal paint can or mixing waste from different jobs in the same container, as unpredictable reactions may occur.


In conclusion, removing paint from exterior surfaces such as brick and wood requires careful consideration of the products used and the appropriate safety measures. While solvents and caustic-based paint strippers are effective, they may also pose health risks and can cause damage to the surface if not used properly. Therefore, it is essential to read the labels and technical and safety data sheets before using any paint stripper, wear appropriate protective gear, and work in well-ventilated areas. It is also important to match the type of paint stripper to the job and to responsibly dispose of the stripping waste. By following these guidelines, you can remove paint from exterior surfaces safely and effectively while minimising the risk of damage or health hazards.

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