In the construction world, there's often a very clearly defined line between B2B and B2C, but there are also companies that straddle the line, providing services and products to both businesses and consumers.
No matter what type of customers you serve, knowing exactly who they are and what matters most to them is the basis of any kind of marketing you do to reach them. A buyer persona is one of the tools we use to help our clients understand their ideal customers better so they can target their marketing efforts.