A homeowner called the Ask This Old House team for unique help. After her son decided to go from being an artist to majoring in agriculture, his old graffiti-style artwork covering her garage walls needed to go. Paint expert Mauro Henrique knows how to handle the job, and helps walk the homeowner through the process of cleaning up her garage walls and ceilings.
How To Paint Over Graffiti
- First, clean the surface of the walls and ceilings with a wet/dry vac. Attach a wand to the hose as well as a brush attachment. Be sure to remove any dust, cobwebs, and other debris that commonly collects on garage walls.
- Use painter’s tape along the edge of any shelves or other built-in objects that you don’t want to paint. Use plastic sheeting to cover these, as well. You can purchase painter’s tape and plastic sheeting combinations to make the job easier.
- Determine which primer to use. If the graffiti is water-based paint, the acrylic primer will work. However, if the paint was oil-based, it might be necessary to use an oil-based primer. Here’s how to tell:
- Choose a spot on the wall with plenty of graffiti.
- Paint a 12-inch by 12-inch square of acrylic primer.
- Apply two coats of the primer and allow to dry.
- If the artwork doesn’t show through the acrylic primer, you’ll be fine using it, which means easier clean-up, faster drying, and less fumes. However, if it shows through, you’ll have to use an oil-based primer.
Note: If you do need to use an oil-based primer, open the garage windows and doors to allow for plenty of ventilation.
- Use a paintbrush to cut in along the edges of the walls and ceilings. Since you’ll be painting both the same color, the cutting doesn’t have to be perfect. Also, cut in around any objects you won’t be painting, like shelves, electrical boxes, and other items.
- Apply the first coat of primer by using the roller, extension handle, and paint trays. Go slowly to prevent splatter, and make sure to overlap previous passes to maintain a wet edge. The first coat can be relatively thick, but don’t apply so much that it pools and runs. Allow the walls and ceilings to dry according to the primer’s instructions before applying a second coat.
- Once the walls are dry, it’s time to paint. Follow the same process as the primer, cutting in along the walls and ceilings as well as any objects that won’t be painted. Acrylic paint should work, so fumes shouldn’t be quite as intense.
- Roll the paint onto the walls and ceilings using the roller, extension, and trays. Work slowly to avoid splatter and overlap previous passes to maintain a wet edge. Once dry according to the manufacturer’s instructions, apply a second coat.
- Carefully remove the tape and sheeting to reveal a fresh, clean surface.
Mauro begins prepping the space by vacuuming and wiping the walls to ensure they’re clean and free of dust. Next, he protects the floors by laying out a drop cloth. He also uses painter’s pre-taped masking film to tape off the shelves on the walls.
Mauro and the homeowner apply an oil-based primer to the walls using 3/4” nap fabric rollers and extension poles to account for the tall ceilings. For the paint, Mauro uses an acrylic flat white paint.
- Painter’s tape
- Drop cloth
- Plastic sheeting
- Primer (oil or acrylic, but more on that in a bit)
- Thick-nap paint roller sleeves designed for concrete surfaces