Grandfathering is a term used to secure lower flood insurance premiums subsequent to a flood zone designation changing. How much you can save depends on several factors with one being the age of your home. If your home was built before your community was issued their first FIRM, requirements for Grandfathering are much more stringent and, therefore, purchasing prior to the map change is critical. To find out when your home was built, click on the link here and type in your address.