A facade is generally one exterior side of a building, usually, but not always, the front. It is a foreign loan word from the French fa├žade, which means "frontage" or "face". In architecture, the facade of a building is often the most important aspect from a design standpoint, as it sets the tone for the rest of the building.From the engineering perspective of a building, the facade is also of great importance due to its impact on energy efficiency.For historical facades, many local zoning regulations or other laws greatly restrict or even forbid their alteration.