Can be produced using a variety of substrates, e.g. weathertex, colourbond steel sheet, aluminium, aluminium composite sheeting, PVC, acrylic, 3D styrene letters/logo and many more to suit your particular application.
As an alternative, of course, there is the traditional signwriting directly onto the building surface.
For a more architectural look, individual letters and / or logos made from acrylic, foam, metal or a combination thereof, would be the way to go.