Cities and suburbs can be dirty places – and unfortunately, getting that dirt off the façade of a building takes more than just a scrub-brush and a bottle of Mr. Clean. How a building is cleaned depends on two factors: what materials the building is made of, and the nature of the grime accumulated on it. There really is no one product that can clean every building.
Know Your Grime
In bustling cities like New York and Chicago, roads are jam-packed with cars and trucks spewing exhaust into the air 24/7. This exhaust often sticks to the exteriors of buildings, and is a common cause of discoloration, staining, and general dinginess. But not every grimy spot you see on a building comes from exhaust.
“No two stains or sources of grime are necessarily the same,” says Aubrey C. Phillibert of property management company FirstService Residential in New York City. “And what one may call a stain another may call efflorescence, or even algae. The white, powdery effect from efflorescence on bricks could be a sign of water damage. Even rust marks can be attributable to oxidizing metal from roof gutters, leader pipes, and even window lintels.”
In most cases, the outside of a building really is dirty because of this environmental pollution. But Mike Landry, a sales representative with Dakota Evans Restoration Inc., in Palatine, Illinois, says that some buildings can repel dirt and air pollution better than others. “Usually, smoother buildings tend to not collect so much dirt, dust, and grime, whereas others that have a brick surface that’s kind of rough, [or] ones that have an exposed, aggregate-type of rough finish tend to collect atmospheric pollution,” he explains. “Sometimes, on a lighter color of building, you can actually see the carbon buildup.”
In New York City, building facades are often made of a different material than the rest of the building. They are meant to withstand a lot, but even the toughest materials aren’t entirely impervious to the elements. Brick buildings are built to absorb a certain amount of water, and then dry out and release that accumulated moisture. Unfortunately, says Landry, some brick buildings were actually made with cheaper alternatives – and that can cause problems in the long run.