Man has built in harm's way since the beginning of time. Ocean shores, river banks, and flood plains are among the more popular areas and they attract the most news when Mother Nature strikes. Even if you are not in a recognized flood area, you still might be in harm's way. Cedar Rapids, Iowa, is a case in point. Flood stage in the Cedar River is at an elevation of 12.0 feet. Major flooding begins at 16.0 feet and the all-time record of 20.00 feet was reached in 1851 and again in 1929. The river crest of 31.12 feet in 2008—caught thousands by surprise.
In earlier times, the reasons for living in flood-prone areas were survival or commerce, which is still the case for many commercial enterprises. In recent history, however, man has built in these locations because they offer tremendous views and have quick access to water recreation; or, the land is inexpensive because of flooding and storms. Man undoubtedly will continue to build in tenuous locations for the same reasons, but we can build better and smarter. No material is better suited than concrete for areas subject to water and storm damage.
The first approach to building in flood and hurricane regions is to build it higher. Many new structures along the Atlantic and Gulf coasts illustrate this principal but structures along rivers also should be built above published flood plain areas. The National Flood Insurance Program requires you to build above the 100-year flood plain to receive insurance, but why stop there? If an additional 2 to 4 feet of elevation will give you better protection, why not do it? The technology to build on concrete piers with a concrete floor deck is readily available and economical in residential construction. The area below the floor makes excellent garage or storage space. If a flood comes, remove the items in the lower area and let the water flow through. Structures built well above the existing grade can be accessed by a series of small planes (decks or patios) connected by stairs to reduce the sense of elevation from the front of the structure.
The concrete floor slab is also a common sense approach to construction in flood-prone areas. Use a decorative concrete slab finish, install an in-slab radiant floor heating system, and cover selected areas with area rugs, which can be rolled up and moved to a higher floor or storage if flood waters come. Rigid insulation can be in-slab, in a sandwich type application, or applied to the underside of the floor slab.
As long as you are going to this much trouble, why not also build concrete walls? Frame walls and wood flooring systems must be stripped of all finishes, reinsulated, and refinished. Concrete walls and floors simply need a good scrubbing and disinfectant (flood waters can often be toxic) and you are ready to repaint or, if you have exposed concrete, reoccupy.
A concrete home built at the proper elevation will give you a home that is built for the centuries, even in harm's way.
—Ed Sauter is the executive director of the Tilt-Up Concrete Association. He can be reached at 319-895-6911 or [email protected].
