Coastal Construction Manual - National Ready Mixed Concrete ...

HISTORICAL PERSPECTIVE 2
Figure 2-19.
Breakaway walls below
the first floor of this
house broke as intended
under the flood forces
of Hurricane Ike (Bolivar
Peninsula, TX, 2008)
Figure 2-20.
Flood opening in an
enclosure with breakaway
walls, Hurricane Ike
(Galveston Bay shoreline,
San Leon, TX)
premiums. Flood insurance premiums for a building located in Zone V are much less when a below-BFE
enclosure is formed by louvers than by breakaway walls. A building with an enclosure formed by louvers is
classified the same as if it had insect screening or open lattice (Figure 2-22), i.e., as “free of obstructions,”
while a solid breakaway wall enclosure results in a “with obstruction” rating for the building.
COASTAL CONSTRUCTION MANUAL
2-27