The positive situation currently experienced by bui lding industry, towards to an industrialization and rationalization, is the resul t of various new technologies of production and management emerged in the 90s, in order to enhance the competitiveness of firms, increase the flexibility in the final products and improve the quality of these. One of these philosophies, specif ically the one is against waste and seeks to add value to the product by understanding needs of the final customer, is known as lean construction. In accord to this, the objective of this study is to propose, through a case study in C. Rolim Engenharia Ltda. ( Brazilian building company), guidelines for internal evaluations at the construc tion site about the level of application, implementation and consolidation of th is philosophy in a company that already has embedded in its organizational culture. The methodology for the development of this proposal includes: characteriza tion of the company which will be evaluated in this case study; formulation of the le an tool checklist according to lean practice of the company; and the definition of the application parameters, such as frequency and evaluation criteria. For this case st udy, the lean audits were applied monthly, from June 2011 to October 2011. These, in fact, point out to reach the goals set, once: all audits have attended more than 80% o f the lean checklist requirements, and performance and areas for improvement in the le an aspect are reported on the Lean Diagnosis generated from the Lean Checklist, besides the fact that the audits and their Lean Diagnoses impact positively the proc ess of making strategic and tactical decisions in the construction site.