How to Build a Deck in a Flood Zone

Permits and Requirements

• Many communities have building codes that cover decks. In some places, the codes cover all decks while other local governments require permits only for decks of a certain height or size. Homes in flood zones may be subject to special building permit requirements or enhanced scrutiny to ensure that decks don't present unreasonable dangers. Before building a deck, contact your area's department of planning and zoning to verify permission requirements.

Building Process

• Once you have the necessary clearance, the process of building a deck in a flood zone is similar to building a deck elsewhere. Construction begins by placing the deck's rim on removable supports then installing vertical support posts that secure the rim. Floor joists are added within the rim's border, and a floor is applied above them to create the deck surface. Railings and stairways are added as the final step before the deck is painted or stained.

Tips and Strategies

• Decks built in flood zones can be protected from the risk of water damage if they are as high as the homes to which they are attached. In flood zones, this level is known as "design flood elevation" (DFE). It is the minimum height for the lowest structural elements of homes, and a good guideline for a reasonable deck height. In some cases, you may not be allowed to build decks that are below DFE unless they are freestanding, not attached to your home. Because flood waters can damage even pressure-treated lumber, building your deck's posts out of poured concrete will help it withstand a flood.

Flood Insurance

• Flood insurance, which is available only to homeowners who live in communities that participate in the National Flood Insurance Program, is an important way to protect the value of your home and its contents. Flood insurance policies, however, do not apply to exterior structures, including decks. This means that any damage to your deck during a flood is your financial responsibility. A damaged deck that fails to comply with building codes may subject you to a fine or force you to remove the deck if you can't afford to repair it to comply with building codes.