Esta es una primera idea para añadirle un segundo nivel a una casa existente, se aprovechan las paredes estructurales del primer piso 

Nuevo 2do piso para residencia

Add 2nd Floor to Existing Residence

This is a first idea to add a second floor to an existing home. To do that is necessary to extend the existing structural walls. All walls in the second floor over 1st floor walls. 

CAD Drawings