Water-Resistant Building Materials

Marine plywood The most water-resistant plywood; it can be used for floor and exterior-wall sheathing.

Exterior-grade plywood Meant to resist low-level moisture, humidity. Not for water saturation conditions.

Greenboard Manufacturers do not consider greenboard (moisture-resistant dry wall) to be a flood-proofing material. It can be submerged for several hours without extensive deterioration and it is only slightly more expensive than normal plasterboard.

Rigid (closed-cell) insulation Will not deform or lose its insulative properties when wet. Can be dried out and reinstalled in wall or floor cavity. Use instead of fiberglass insulation.

Synthetic baseboards Use instead of wood base.

Galvanized nails Will not rust after being in floodwaters. Use at all locations up to three feet above the Base Flood Elevation.

Metal doors and frames Will not warp if saturated. May rust in spots, but this can be sanded out and repainted. Use at all doorways, especially exterior.

Metal and vinyl windows Will not warp if saturated.

Sheet vinyl flooring or tile Adheres to marine or pressure treated plywood underlayment with waterproof adhesive.

Indoor and outdoor carpet Use with synthetic carpet pad. Do not permanently fasten down.

Galvanized drywall screws Will not rust and allow easy removal and reassembly of interior walls. Use instead of standard drywall nails.

Brick, concrete Not damaged by water saturation, but must be used in conjunction with a waterproof membrane.

Plastic wood Made of recycled plastics. Waterproof and dimensionally stable. Check building code for acceptable uses.

Pressure-treated lumber/ plywood Relatively stable in water saturation conditions. Will not sustain heavy damage but may warp. Plywood second only to marine plywood in water-resistance. Use at all flood-levels. Moisture-resistant material below the Base Flood Elevation. (Note: If treated lumber is used, protective gloves must be worn during installation, and a protective barrier such as drywall must be placed between the treated lumber and living space.)

Building Materials to Avoid When Floodproofing

♦ Fiberglass or cellulose installation

♦ Cork or corkboard

♦ Gasoline, motor oil, weed killer, pesticide, lye, drain clear, swimming pool and other chemicals

♦ Linoleum

♦ Particle board, plywood, chipboard, fiberboard, paperboard, strawboard, Masonite paneling

♦ Wallboard, plasterboard, drywall, gypsum

♦ Wallpaper

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