Why should a building's facade be cleaned? The issue of aesthetics first comes to mind. After all, a clean building simply looks better than a dirty building. A clean building presents a more hospitable front - and, therefore, a more attractive real estate prospect - to the public. Just as we put our best foot forward with a neat, kempt appearance, a building looks its best when free of the grime, pollutants, and staining that shadow its most visible - and often, most vulnerable - attribute, its facade.