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Graffiti Removal
Every year, building owners, neighborhood groups and public agencies spend millions of dollars dealing with graffiti in public places. In the urban landscape, indifferently matched rectangles of new paint are common — and just about as unattractive as the graffiti itself.
by Gail Elber
for a property owner than finding graffiti on the walls of a building — except maybe coming back and finding it again after spending a lot of time and money on removal.
Every year, building owners, neighborhood groups and public agencies spend millions of dollars dealing with graffiti in public places. In the urban landscape, indifferently matched rectangles of new paint are common — and just about as unattractive as the graffiti itself.
These patchwork cover-ups are by no means the best solution to the problem. In many cases, a professionally applied anti-graffiti coating is the most cost-effective way to protect buildings, structures, and interiors from defacement. These coatings can reduce graffiti cleanup from a big project to a morning-after spritz-and-scrub.
Three kinds of anti-graffiti coatings are available: permanent, semi-permanent, and sacrificial.
Permanent coatings, such as Dumond Chemical Company’s CPU 647, Sherwin-Williams’ Diamond Clad Clearcoat Urethane, Graffiti Master Products’ Perma-Master, Fiberlock’s Street Fighter Premium, and Genesis Coatings’ GCP-1000 are meant to last through many cleanings with solvent. Supplied as two parts that you mix before applying, they form a hard surface, usually polyurethane, that spray paint and ink can’t bite into. Permanent coatings are the most expensive — often exceeding 90 cents per square foot for material alone — and the most exacting to apply, because they are supplied as two parts that have only a few hours’ pot life after mixing.
Semipermanent coatings can be cleaned with solvent several times, but each cleaning wears away a little of the barrier, and you must reapply them after a few cleanings. Acrylic products, such as Graffiti Master’s Acryli-Master and Fiberlock’s Street Fighter, fall into this category.
Sacrificial coatings are water-based and create a smooth wax or polymer surface that keeps paint or ink from penetrating to the substrate. Graffiti Melt from Genesis Coatings and SC-101 from Dumond are examples. If the surface is defaced with graffiti, maintenance people can wash the graffiti and the whole coating off with hot water and reapply the coating. They needn’t wash off the whole wall — they can just clean the affected area and spray or roll on a new patch of coating. Graffiti Melt can even be reapplied with a spray bottle. Coatings of this type can cost less than ten cents a square foot to apply.
Wood, unfinished masonry
or concrete
For any immobile object, even a tree, there is an appropriate anti-graffiti coating. Unpainted wood (including trees) should be coated with a paraffin-based sacrificial product that will flex with the wood’s expansion and contraction. Acrylic or polyurethane coatings will crack.
Not every manufacturer recommends their product for unfinished masonry or concrete, but Dumond Chemical Company has a rubber-silicone based product called Dumond Anti-Graffitiant that is especially formulated for porous surfaces of this kind. The Audubon Society’s headquarters, a brownstone building in a graffiti-ridden area of New York City, was coated with Dumond’s Anti-Graffitiant in 1994. The stone surface has been cleaned with solvent many times a year since then without needing recoating.
For painted surfaces, permanent coatings are generally best. If you have a water tank that is due for complete repainting, for example, you can protect it with a paint system whose outermost layer sheds graffiti. Sherwin-Williams has a product called Diamond-Clad Clear Coat that is designed to function, clear or tinted, as the top layer of the company’s multilayer urethane paint system. However, the company doesn’t recommend applying it over other brands of paint.
Painted surfaces can be protected with one of the two-component polyurethanes. Old marks should be removed or covered with a graffiti-blocking primer. If you’ll be applying the coating over old paint, make sure the underlying paint is clean and in good condition, or you’ll be looking at any dirt or chips preserved under that coating for a long time. Some coatings can be given an opaque color to avoid that problem. Permanent coatings impart ultraviolet resistance and impact resistance to the underlying paint, helping to keep it from fading and chipping.
If the underlying surface is painted or sealed, consult the manufacturer about whether their product is suitable. For example, oil-based paints must cure for six months before polyurethane is applied over them. The manufacturer may recommend testing the coating on a small area first. |
