How to Check Buildings After a Flood

by Marie Richie



When entering any damaged building, you should be prepared for extreme hazards and floods are no exception. Wear comfortable and close-fitted clothing with thick-soled shoes or boots. It is advisable to wear a helmet to prevent injury from falling plaster and sodden ceilings. Carry a battery or crank driven flashlight if you must enter at night. You will also need to bring some tools. Handy items include but are not limited to: Broken natural gas lines present one of the greatest hazards. Do NOT smoke or use a light source with an open flame or spark. Sulfur compounds in natural gas lines will alert you to broken pipes. If you smell rotten eggs, look for a switch to turn the gas off at the meter or tank.

Even if you don't have a gas leak, it's important to open doors and windows as soon as possible to allow toxic and flammable gasses to escape along with the mildew stench. This may be very difficult if the wood is swollen with moisture. If the doors won't open, unscrew the hinges and pull them off. If the windows won't budge, pull the side strips off and pull the entire sash out. If electricity is available, a fan will help.

Some very serious looking problems have a relatively simple fix, whereas some minor looking issues may require bulldozing and starting over. The most critical parts of the structure can be broken down into four categories: Since the stability of the entire structure depends upon a solid foundation, you'll want to spend extra time in evaluating it's integrity. The University of Michigan Extension Service recommends flood-damaged neighbourhoods pooling their resources to hire a professional inspector to check the foundations in the area. However, there are some simple things you can assess yourself. Before you can check, make sure crawl spaces are completely free of standing water by pumping it out or waiting for it to recede.

Obvious cracks and buckles indicate the ground beneath has shifted. Even if the foundation appears solid, holes may have opened up beneath it that will cause future damage if not addressed. Be especially careful when inspecting around the "footings" at the corners and load-bearing intervals. Like the heel of a high-heeled shoe, they carry a tremendous amount of weight per square inch of surface area and, are prone to large washouts around them. Use gravel to fill in holes that have opened, up to 12 inches from the footings. If your building uses piers, be sure they've not shifted. Badly damaged foundations may need to be braced with rock and steel bars before any other work can be done.

Once inside, check the walls and ceilings. If they are intact, you'll need to clean them off with a scrub brush or mop before they can be fully inspected and to prevent silty clay from drying on them. A hose can be very handy for the initial inspection process if there is running water. Always work down from the top floors with damage.

When the walls are cleaned off, you can check the amount of bowing with a level. Bubble-types and laser types are now available - some experts use a special weight on a string. No matter what you use, you'll be able to quickly tell where immediate repair is necessary. Walls may be temporarily braced or repaired with mildew resistant materials like redwood, cedar and pressure-treated wood.

To dry the walls more quickly, try pulling the mop-boards up. If the drywall or plaster is loose or sodden-through, it will need to be pulled off to inspect the insulation and studs. Flooded insulation must be carefully disposed of with skin and lung protection. Under no circumstances should you seal the moisture in with a fresh coat of paint. It may take months for wet wall and ceiling materials to dry out enough. Missing interior walls may be temporarily sealed with plywood.

Wooden floors must be dried slowly to prevent cracking and splitting. An even temperature of 60 to 70 degrees F should be applied if possible. During the drying process, which could take months, nails may be driven into areas that are bulging up. When the floor is completely dry, you may bring a rotary sander in to refinish the surface and smooth out warped patches. A plane may be very carefully used to level out buckled sections. Badly damaged wooden surfaces may be covered up with carpet or linoleum after the wood is thoroughly dried out.

Concrete floors may crack if the foundation has shifted even a small amount. If the damage isn't too bad, you may repair the cracks with a home-mixed concrete. Use very fine sand with no gravel, mixing at about half the usual amount to create a "rich" mixture. If there are more than a few cracks, the whole floor will have to be broken up, removed and re-poured.

The first order of business for damaged roofs is to keep more water from coming in. Plastic sheeting and tarps may be used temporarily to keep the water out. Be sure edges are tucked in so water isn't carried under adjacent shingles. Small holes may be plugged with any number of commercially available "patching compounds." Metal or "spaced deck" roofs will have to be replaced as entire sections.