Mark Atkins, director, LTP, explains how to remove graffiti without damaging common urban surfaces
There are lots of positives about long summer evenings and warmer weather, but not when it comes to graffiti. The summer months bring an increase in the rates of graffiti vandalism and tagging, with activity rising year-on-year.
Graffiti ‘artists’ tend to use fast-drying, high-pigment aerosol spray paints, permanent markers and bitumen-based paints. All of these are hard to remove from porous surfaces because they penetrate deeply into the material’s pores and form strong, durable chemical bonds with the substrate, acting like a stain rather than a surface coating.
Common urban surfaces, like stone walls, brickwork and concrete, are all porous so they readily absorb graffiti. They’re often sensitive, so strong solvents, alkali or acid cleaning solutions can erode the surface and should be avoided. Other removal methods, like sandblasting or high pressure steam cleaning are abrasive and can cause additional damage to the underlying surface.
In order to safely remove graffiti from these surfaces, you need to use a non-caustic solution, like Solvex. These solutions are generally applied with a paint brush or by dapping with a cloth. The treatment is applied in manageable areas of no more than five square metres and it’s important not to brush it out; keep the application generous. The solution should then be left to dwell on the surface for the specified time – generally up to 30 minutes. If the surface starts to dry within this timeframe, apply more treatment. Then, use a stiff brush or an abrasive nylon pad to remove the softened paint and repeat the process if any unwanted material remains. After treatment, wash down the surface with a suitable intensive cleaner, rinse with plenty of water and leave to dry.
After cleaning stone to remove graffiti, we’d normally advise the application of a suitable impregnating sealer that does not alter the natural appearance of the surface that’s being protected. This also helps to make any future clean-up much easier by reducing the risk of absorption.
