In general, the advisories will require homes inside the levee system to be built three feet above the local grade, or at the current required elevation, whichever is higher. The ruling effects new construction and renovation paid for by flood insurance or federal aid when a home suffered more than 50 percent damage.What we will probably see is that the slab on grade home will become an endangered species and flourishing raised cottages at least in middle-class to lower middle-class neighborhoods. In areas where lot sizes are larger, we'll probably see houses built on three to five or more feet of fill where the homeowner has more resources to spend.
The reason that we see so many slab on grade homes and so few raised cottages is cost. Building a house on piers is more costly than pouring concrete on the ground. For the new FEMA map requirements to not put an undue burden on the middle-class homeowner, contractors, building material manufacturers, engineers and architects need to investigate ways in which the costs of building raised houses could be reduced. If we can do that, people may not be forced to decide between building a home and building a home that will flood.