What is the definition of façade?

A facade (or cladding) is a vertical side of a building, usually the front one.  
It gives the tone of the whole building. The design of facades can be protected and subject to local regulations, for instance, its height, projection of balcony and roof, sometimes its colour... Check with your local authorities if your project matches these local requirements.  
Facades are of course very important for the insulation, and the waterproofing of the building, but also to bring natural light inside the building. Material for the facade has to be carefully selected according to your needs. 

Another facade definition is linked to its contribution to the structure and stability of the building:
- light cladding: built with lightweight materials (metal, glass, wood panels...), that does not participate in the building stability. 
- heavy masonry facade: built with bearing masonry elements like bricks, dressed stones and cement mortar, sealant.