Having to remove graffiti from buildings is a common problem in large cities like Minneapolis and St. Paul. Also referred to as “tagging,” graffiti is painted by people who don’t typically see their “artwork” as damaging or criminal. Unfortunately, most property owners take a much different view and typically see graffiti as vandalism that requires expanding resources to clean up. Environmental factors like auto exhaust, atmospheric pollution, road salt, dirt and grime, rust from water, and biological organisms like mold and mildew can also result in damage.
All of these can take a toll on a building’s appearance, resulting in unsightly stains that make the property look old and dirty. However, pressure washing and chemical cleaning can take care of most stains, and there are ways of effectively removing graffiti from storefronts and historic buildings. For best results, paint should be removed as soon as possible as the longer it is left on, the harder it is to remove. As a general rule, the longer the graffiti has been on a building, the stronger the solvents must be. When trying to remove graffiti, commercial masonry contractors suggest keeping these rules in mind:
1) If the graffiti is not coming off, try a different method.
2) Before you try tackling a big job, test a small area first. If the graffiti can’t be removed from a small spot, it won’t come off a larger area.
3) Rub gently. If you have to scrub hard, the cleaning agent is not strong enough, or the graffiti has been on too long to be removed with solvents or cleaners.
How to Remove Graffiti – Removing Spray Paint From Glass
Removing paint from windows is one of the easier issues to deal with. However, the technique used depends on the window material.
Glass or Clear Acrylic
Paint can easily be removed from glass with a razor blade. While a razor blade won’t scratch glass if it is held flat against the surface, blades can scratch softer surfaces like acrylic or polycarbonate. However, removing paint from clear acrylic, often referred to as “Plexiglas,” requires more care. Here it is best to use a solvent, like paint remover, mineral spirits, or turpentine. Mineral spirits work well at removing fresh paint, but turpentine must be used once the paint has started to cure. After the paint has cured completely, paint remover must be used. Note that methylene chloride is the main ingredient in most paint removers and is very caustic; this can give you chemical burns with prolonged skin contact, so be sure to wear gloves whenever using paint removers.
Removing graffiti from fiberglass can be tricky as weaker solvents don’t have the strength to penetrate the fibers, and the stronger ones can weaken the bonds and damage the surface. It is best to apply straight paint remover to a rag and rub the surface in circular motions. Stop and wash the surface often and thoroughly with mild soap and warm water to keep the solvent from soaking into the structure.
Graffiti can usually be removed from painted wood if it has been on less than a day or two. Begin with a weaker solvent like mineral spirits and work your way up to paint remover. Remember that the stronger the solvent, the greater the chance it will also remove the paint under the graffiti. You will probably have to paint over the graffiti if it has been on for more than two days. Be sure to use a stain-killing outdoor primer over the graffiti before painting. Apply a sealer coat so that any future taggings can be easily removed.
Brick and Masonry
Because it is so porous, removing graffiti from commercial masonry requires using a high-strength remover. Work the solvent into the surface well with a wire brush, let it sit according to the manufacture’s instructions and then rinse the surface with a pressure washer. Alternatively, or if the solvent does not work, most graffiti can be removed with pressure blasting. As brick and masonry can be damaged by aggressive mediums, like bead blasting, always start with the least aggressive medium, such as soda, and work up to more aggressive types. Professional stone masonry restoration contractors recommend applying a sealer to keep the paint from future taggings from penetrating the material’s pores.
Graffiti can usually be removed from metals like steel, bronze, brass, and copper, but the most effective method will depend on the type of metal and whether or not it is coated.
- Uncoated Metal
There are a variety of techniques to remove graffiti from uncoated metal surfaces. Inks and some spray paints can be removed with products marketed as graffiti removers. Apply cleaners with a cloth, turn the cloth frequently, and rinse with a pressure washer. Note that uncoated metal surfaces are often sensitive to pH and alkaline cleaners can darken or stain the metal, so be sure to use a pH-neutral cleaner.
- Painted Metal
There are graffiti removers designed to dissolve uncured paint. Note that paint will typically become dry to the touch in five minutes to an hour, but it takes 24 hours or longer to cure. This is why it is essential to try to remove graffiti as soon as possible, as once it cures, it becomes much harder to get off. Graffiti that has cured on painted metal typically requires repainting the surface.
- Stainless Steel
Brick, stone, and masonry graffiti remover will remove most graffiti types from stainless and galvanized steel and brass, bronze, and copper. Apply with a rag, rub and rinse thoroughly with a pressure washer.
Epic Masonry Restoration | Commercial Masonry
Because some of the techniques covered here, like using a pressure washer or blaster, can damage surfaces if not used correctly, you may want to consider hiring a professional. This is especially important for high-profile commercial buildings and those with historical value. A pressure washing contractor can effectively remove graffiti, mineral deposits, and stains without damaging your property.
Epic Masonry Restoration has years of experience removing graffiti from commercial buildings and performing historic restorations in the Minneapolis and St. Paul area. We are experts at pressure washing, chemical cleaning, and applying protective coatings to guard against future vandalism. It is our job to help your property look its best. We offer various services that will enhance your building’s visual appeal and extend material life so your property will make a positive first impression. Call us at 612-353-4646 or visit them online at epicmasonryrestoration.com.