The Function point analysis (FPA) method is the preferred scheme of estimation for project managers to determine the size, effort, schedule, resource loading and other such parameters. The FPA method by International Function Point Users Group (IFPUG) has captured the critical implementation features of an application through fourteen general system characteristics. However, Non- functional requirements (NFRs) such as functionality, reliability, efficiency, usability, maintainability, portability, etc. have not been included in the FPA estimation method. This paper discusses some of the NFRs and tries to determine a degree of influence for each of them. An attempt to factor the NFRs into estimation has been made. This approach needs to be validated with data collection and analysis.