The aim of this work is to provide data for improving the planning of office buildings maintenance. We got the maintenance record of a large-scale office building that lasts about 11 years since building completion. The record includes the data of 10,937 faults or defects. Using this record data..the features of the occurrence and the term to repair of faults or defects are grasped. The record data include the information about the outsourcing of repair work. This paper also presents the results of the analysis concerning to the outsourcing ratio that will relate to the planning of number of maintenance staffs.
