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Flooding & Flood Risks


How to Save Money with the Grandfather Rule

If a new Flood Insurance Rate Map (FIRM) shows your high-risk property is at a greater risk for flooding than shown on the previous map, your flood insurance rates will likely change. In general, flood insurance rates for higher-risk areas are higher, but there are ways to save money with the NFIP Grandfather Rule.

Structures built after the community's first flood map was issued (post-FIRM) have two opportunities to lock in the flood zone or Base Flood Elevation for insurance rating purposes:

  1. You can purchase a policy before the new maps take effect, or
  2. You can use the Grandfather Rule if you have proof that your home was built in compliance with the flood map that was in effect at the time of construction. Your insurance agent can help produce the necessary documentation.

Structures built before the community’s first flood map was issued (pre-FIRM) must have a policy in place before the new map takes effect to qualify for grandfathering.

In some cases, using the new flood map to rate your policy may actually result in a lower premium than what grandfathering applies. Be sure that your insurance agent checks all options.

Learn more about what happens when maps change.

Mapped from a high-risk area into a moderate- to low-risk area? Discover how converting your policy can save you money and keep you financially protected.

Mapped from a moderate- to low-risk area into a high-risk area? Discover how the Newly Mapped procedure can save you money and keep you financially protected.

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For flood insurance rating purposes, a primary residence is a building that will be lived in by the insured or the insured's spouse for at least 80 percent of the 365 days following the policy effective date. If the building will be lived in for less than 80 percent of the policy year, it is considered to be a non-primary residence.

How Can I get Covered?

  • Rate your risk
  • Estimate your premiums
  • Find an agent

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Last Updated: Monday, 21-Sep-2015, 8:43 AM (EDT)

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