How to remove graffiti with a pressure washer

January 9, 2025

BISON Santy

Hello, I am Santy, the funder of bisonclean.com. I have been in cleaning machinery field for more than 5 years now, and the purpose of this article is to share with you the knowledge related to pressure washer from a Chinese supplier's perspective.

Graffiti and potential damage to surfaces such as brick and stucco are not only unsightly but also a difficult task for property owners and communities to deal with. In this context, pressure washers emerge as an effective and efficient solution. The pressure washer uses high-pressure water jets to remove stubborn graffiti from a variety of surfaces including concrete, brick, and wood. Compared with ordinary removal methods, using a pressure washer is not only more efficient but also minimizes damage to the surface material.

This fast method of graffiti removal is essential to maintaining a clean and pleasant environment, preventing further damage from spray paint, and saving maintenance costs. In this blog, BISON will cover the steps to effectively remove graffiti using a pressure washer, from types of graffiti, tool preparation to cleaning maintenance to help keep surfaces in tip-top condition. Let’s dive right in!

Assessment and preparation before graffiti removal

1. Surface identification and assessment

There are a variety of graffiti products available, so graffiti removal begins with determining the type of graffiti. The most common types of graffiti are as follows:

Spray paint: The most common type of graffiti. For fresh spray paint, high pressure water may be sufficient. However, dried spray paint is difficult to remove and requires the correct solvent and pressure cleaning technique.
Permanent markers and pens: Like spray paint, the ink used in markers and pens dries quickly, which can result in a lasting residue that may require specific cleaners to be effectively removed.
Acrylic paint: It is often used by artists, and this type of paint is sometimes easier to remove than spray paint, depending on the surface.
Stickers and decals: Less common, it tends to create a residue that is difficult to remove and may require the use of a special cleaner.

So what is the difference between different surfaces?

Metal: Metal surfaces are smooth and generally more resilient, requiring different techniques or cleaning solutions to avoid scratches.
Concrete: Concrete is very porous and can absorb paint, making it difficult to completely clean without special treatment.
Brick: Similar to concrete, the texture and porosity of brick can complicate removal, and care must be taken to avoid damaging the surface.
Softer materials like wood or stucco: Wood surfaces are porous and easily damaged, so low-pressure, gentle cleaning methods are required, and special care may be required to prevent warping.

Considering the sensitivity of various surfaces is critical to determining the correct pressure setting and cleaning method. For delicate surfaces (softer materials like wood or stucco), consider using low-pressure, gentle cleaning techniques and cleaners.

2.Safety precautions

For full operation, BISON reminds you to prepare: safety glasses, gloves, and respiratory protection.

At the same time, to protect adjacent surfaces from water and cleaning agents, cover them with waterproof or plastic sheets. Remove nearby plants, furniture, windows, or surfaces that should not be exposed to high-pressure water or cleaning solutions to prevent contamination.

3.Required equipment and materials

Pressure washer specifications

We recommend using a BISON cold pressure washer with a PSI (pounds per square inch) rating between 1,500 and 3,500 to remove graffiti. Or use a hot water pressure washer with a jet temperature of up to 110°C. The combination of pressure and heat will remove stains without damaging the underlying surface.

Cleaning solutions and pretreatment

Specific graffiti removers or strong detergents can help break down the paint. Make sure to choose a solution that is compatible with both the type of graffiti and the surface you are cleaning. Old graffiti that has been on the surface for more than a few days may require the use of a chemical cleaner to loosen the paint (leave it for 5 to 15 minutes) before high-pressure water is used to remove it.

Other tools

Nozzles: Different nozzle attachments can adjust the pressure and width of the spray for more precise cleaning (25 to 40-degree nozzles are generally recommended for most surfaces). If the graffiti is on brick or masonry, a turbo nozzle will be most effective and can cut removal time by about half.

Plastic scraper or stiff-bristle brush: Helps remove more stubborn paint.

High-pressure cleaning process

#Step 1: Pre-Cleaning

Before you begin the removal process, it is critical to select an inconspicuous part of the graffiti to test. This will help determine how the surface will react to pressure washing and cleaning agents, and make adjustments if necessary. Use a brush or broom to remove loose dirt, dust, or debris from the area as necessary, increasing the effectiveness of the cleaning.

#Step 2: High-pressure cleaning technique

Recommended pressure: Set the pressure between 1,500 and 3,500 PSI for the type of surface you are cleaning, always starting at the lower end and working your way up if using a cleaning solution.

Recommended distance: Start high pressure cleaning about 2 feet from the surface. This distance helps control the pressure while reducing the risk of damage, then move closer until the graffiti is gone.

Spray angle: Hold the nozzle at a 45-degree angle to the surface. This angle helps lift the paint without pressing it deep into the material.

Movement pattern: Use a systematic movement pattern when cleaning, starting on the left side, then moving to the right, and from top to bottom. This ensures even coverage and prevents streaking.

#Step 3: Post-cleaning treatment

After high pressure cleaning, proper follow-up procedures are very important. We need to check the cleaned area for any residual paint or stains, and if any residual stains are found, repeat the cleaning process in that area. Finally, rinse the entire area with clean water to ensure that all cleaning solutions and residues are removed.

After-care and maintenance

Repair and maintenance needs assessment: Look for signs of wear, chipping, or other damage in the cleaned area. If damage is found, the condition needs to be assessed, and consideration must be given to whether to patch, paint, or resurface to restore surface integrity.

Prevention of future graffiti: Select an appropriate anti-graffiti coating to provide a protective barrier on the surface, or use physical barriers, creating fences, walls or planters to discourage vandalism. A regular surface cleaning program can also deter or prevent graffiti.

Conclusion

Removing graffiti with a pressure washer is a quick and thorough cleaning solution. You only need to follow the cleaning steps explained above and take timely action to prevent further damage to the graffiti surface. Graffiti removal requires patience and persistence to achieve the full effect. BISON encourages everyone to consider using a pressure washer as a primary tool to solve graffiti problems.

If you are a dealer who is looking for a suitable pressure washer, please contact BISON today. As a professional pressure washer manufacturing company in China, we have rich production and sales experience to escort your business. Gasoline pressure washer, diesel pressure washer, electric pressure washer, hot water pressure washer and other pressure washers are available directly from BISON, or customized exclusively.

FAQs About Remove Graffiti With A Pressure Washer

How to determine the type of graffiti?

The easiest way is to use methylated spirits. Dampen a rag with the spirit and wipe the graffiti paint to see if the paint rubs out. If the paint rubs out onto the rag, it is acrylic paint, if the paint does not rub out, it will be oil-based paint.