Samples of requests for approval. Use the following samples to guide you when writing a request for approval letter.Department of Buildings Forms. These forms and documents are provided to assist you with applying for a building permit in the City of Chicago. I am writing to confirm my acceptance of your employment offer on April 20 and to tell you how delighted I am to be joining XYZ Corporation in Chicago. Approval letters are generally sent to homeowners who want to make an architectural change to the outside of their homes. A Request for Approval Letter is a formal document used to seek official permission or authorization from a supervisor, department head, or governing authority. In this article, you'll find everything about different types of requests for approval and easy ways to successfully submit them. Submit a new Permit Application using this website. Apply Find Permit Search for an existing Permit that is not already in your list of permits.