The challenge of restoring giant public murals

HostI was walking by that old brick wall on the corner near my house the other day. You know the one with the huge blue whale painted on it? It used to be so bright, but now it's just a mess of grey flakes and peeling skin. It made me wonder why nobody just goes up there with a bucket of paint and fixes it. I mean, we fix potholes and we fix signs. Why is a wall so much tougher?

GuestWell, the first thing to know is that a wall isn't just a flat, dead thing. It breathes. Especially those old brick walls you see in the city. They soak up rain like a sponge and then they try to sweat it out when the sun comes up. If you just slap a fresh coat of house paint over an old mural, you're basically wrapping the building in plastic. The water gets trapped inside, the salt in the bricks starts to eat away at the back of the paint, and within a year, the whole thing just pops off in big chunks. You're not just painting a picture, you're trying to manage a living, breathing skin that's constantly moving.

HostI always thought you just needed a heavy duty spray and some fresh cans of paint to get the job done. Are you saying the wall itself is actually fighting the art?

GuestIn a way, yeah. It's a slow motion war. You have the sun beating down on it with those harsh rays that bleach the color right out of the red and yellow paint. Then you have the wind sandblasting the surface with grit and dirt from the street. But the biggest fight is from the inside. Concrete and brick are full of salts. When water moves through the wall, it carries those salts to the surface. They turn into these white, crusty crystals that push the paint away from the wall. If you want to fix a mural, you have to spend weeks just cleaning that junk off and making sure the wall can still let air through, or your new work will just die the same way the old stuff did.

HostWait, so the salt is coming from inside the wall? That sounds like a lot of prep work before you even get to the fun part. But once you have a clean surface, is it not just a matter of matching the colors?

GuestYou would think so, but think about the size of these things. When you're standing on a metal frame fifty feet in the air, you're about six inches away from the wall. You're looking at a blue dot that's supposed to be part of an eye, but that eye is six feet wide. You can't see what you're doing. You have to climb all the way down, walk across the street, look at it, then climb back up and hope you remember exactly which shade of blue you were holding. It's like trying to do a puzzle while looking through a straw. If you get the curve of a line wrong by even an inch, the whole face looks broken when you stand back on the sidewalk.

HostCan you not just use a drone or a camera on a stick to see if it's straight while you're up there?

GuestPeople try that, but it's not the same as the human eye. The way light hits a wall changes every hour. A color that looks perfect at ten in the morning might look like mud by three in the afternoon. Plus, you have to think about the original person who painted it. Their brush strokes have a certain rhythm. If I come in and try to mimic that, I might be too stiff or too loose. You can always tell where a new hand has tried to copy an old one. It feels like a song where someone is singing just a tiny bit off the beat.

HostI see what you mean, but if I paid for a fix, I would want it to look brand new. I would want those colors to pop like they did on day one. Is that not the whole point?

GuestThat's where it gets really sticky. There's a big debate about whether we should make it look new or just keep it from getting worse. If you make it look too perfect, you lose the history of the piece. It starts to look like a plastic toy instead of a piece of the city. We call the old paint ghosts. Sometimes, you want the ghost to show through a little bit. It shows that the art has lived through the years. If you just paint over everything with bright, flat colors, you might kill the soul of the work. You're trying to find a balance between a bright future and a respected past.

HostThat sounds like a lot of pressure. You're part painter, part scientist, and part judge. And I guess you have to do all of this while the city is moving around you.

GuestOh, the city never stops. You have cars splashing mud on your fresh work, people asking you questions every five minutes, and birds that don't care about your art at all. You're also dealing with the fact that the original paints might have had lead in them or other stuff that we don't use anymore. You have to find a way to make the new, safe paint stick to the old, weird stuff without the whole thing bubbling up. It's a puzzle that changes every time the temperature drops or the wind picks up. It's a lot of work for something that's ultimately going to fade again anyway.

HostIt's a bit sad to think about it that way, that it's all just a temporary fix against the sun and the salt.

GuestEvery mural is a ticking clock, and the goal is just to give it a few more good years for people to enjoy.

HostThe whale on my street might be fading into a ghost, but at least now I know why it can't just be fixed with a quick spray.

GuestConcrete eventually wins every fight, but the paint sure gives it a run for its money.

HostThat blue whale on the corner still has a lot of life in it, even if the salt is trying its best to turn it back into a plain old wall.