August 15, 2019 | Integrity Services As Integrity Services expands its commercial cleaning business into the Chicago area, we asked ourselves, “How long would it take to clean the Willis Tower, top to bottom?” Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Comment Name * Email * Website Save my name, email, and website in this browser for the next time I comment. Notify me of follow-up comments by email. Notify me of new posts by email.