I understood. My reply wasn't very clear.
Yes, you need to consider what the insurable value WILL be with the loan proceeds improving the building. Otherwise, you'll have knowledge that the insurable value is more than what you're requiring.
Think about this: I have a bare lot. I'm borrowing to build a $200,000 house on it. The insurable value before the loan is $0. The insurable value after the construction is complete is $200,000+. Flood insurance must be required for the estimated value of the completed home. Then, upon first renewal, the flood insurance should be re-evaluated based on the RCV of the completed home.