Garage doors at the beach: salt air and floods

It goes after the steel parts that carry the door's weight. DASMA's sheet on spring life says rust reduces the effective area of spring wire, and with it the spring's strength, and leaves corrosion pits where fatigue cracks start. A DASMA trade article adds that bare oil-tempered springs eventually rust because they have no coating, that coatings delay rust rather than prevent it, and that galvanized springs may resist it better.

Cables and bottom brackets sit at floor level, where water, sand and wet leaves collect. DASMA tells homeowners to look at the cables where they attach to the bottom brackets on both sides; frayed or worn cables are in danger of breaking, and because of the spring tension they should be replaced only by a trained technician. The bottom brackets are under extreme tension too, so look but don't loosen. Rollers and hinges belong on the monthly look-over as well: DASMA's homeowner guide says to check hinges, rollers, springs and panels for wear or damage.

Near the surf, aluminum has the edge on rust; farther back, galvanized steel makes sense. Haas builds its Residential Aluminum 360 Series from what it calls rust- and corrosion-free commercial grade aluminum, with tongue-and-groove section joints and a wide choice of glass for a full-view look. Its Insulated Aluminum 5000 Series pairs corrosion-resistant aluminum with polyurethane insulation, at a tested U-factor of 0.110 for the 2-inch 5200 and 0.097 for the 1-3/4 inch 5700, and American Tradition 9200a models bring the carriage house look in 24-gauge aluminum.

Steel brings more choices. Haas's Insulated Steel 2000 Series wraps 2 inches of polyurethane in 26-gauge galvanized steel, with a tested U-factor of 0.094, and comes in 26 colors and 9 panel options, against 3 colors and 4 panel options on the 5000 Series. Haas's 700 and 600 Series are galvanized steel too. One trade-off for aluminum: DASMA notes it expands more with heat than steel, which can add to thermal bowing on insulated doors.

Whatever the skin, the door still runs on springs, cables, drums and brackets, and that's where salt does its damage. FEMA's coastal guide recommends hot-dipped galvanized or stainless steel hardware near the ocean and warns against accepting any product just because it's labeled corrosion-resistant, so ask how the hardware on a door is protected.

Keep salt off it, keep it lubricated, and keep it closed. DASMA's spring-life sheet says doors near a saline coastal location should be kept closed where possible, and that regular lubrication of springs, as the manufacturer's instructions require, helps them reach their cycle life.

• Rinse it. FEMA notes that rain washes salt off exposed metal while sheltered surfaces collect it. After a salty blow or a storm, rinse sand and salt off the door face, the bottom edge and the bottom seal with fresh water, keep water off the opener, and let it dry.
• Lubricate on schedule. IDA suggests a small amount of spray lubricant on the hinges, rollers and tracks twice a year, and DASMA suggests a spray lubricant made for garage doors on noisy springs. Your door's instructions are the final word.
• Look it over monthly. With the door closed, IDA says to look over the springs, cables, rollers and pulleys, paying close attention to cable wear or fraying.
• Keep hands off the tension parts. DASMA's guide says not to loosen or adjust bottom brackets, red fasteners, cables or supports; rust on any of them is a call for a technician.
• Book a yearly visit. DASMA recommends an annual visit from a trained door systems technician on top of the monthly owner checks.
• After high water, have the cables and springs looked at before you run the door, and make sure the photo eyes still line up.

For new construction and substantial improvements in an A zone, a garage below the base flood elevation is an enclosure, and federal rules limit its use to parking, building access or storage. It also needs flood openings that let water in and out on their own: at least two, with a total net area of at least one square inch for every square foot of enclosed area, and the bottom of each no higher than one foot above grade, unless an engineer or architect certifies another design.

The garage door itself doesn't count as a flood opening, FEMA's flood openings bulletin says, because someone would have to open it, and neither do the gaps around it or a door that opens when it senses water. Vents can be built into the garage door when the walls lack room, but FEMA warns that later owners may replace those doors with solid ones by mistake. If your door has vents, the new one needs them.

In a V zone, the high-hazard strip along the oceanfront, the space below the lowest floor of new or substantially improved homes must be left open or enclosed with breakaway walls, lattice or screening built to collapse under storm loads without damaging the house above; breakaway walls carry a design safe loading resistance of 10 to 20 pounds per square foot. FEMA's breakaway wall bulletin treats a standard residential garage door as a breakaway panel there but still expects a door rated for the building's wind loads, and DASMA notes the breakaway rules can override wind and debris requirements. The local floodplain administrator, normally at the town hall or county office, makes the call on your garage.

Access first, then safety. Change the keypad code between guests and clear out remotes that have gone missing, then run the two monthly safety tests: a 2x4 laid flat under the closing door, which must make it reverse, and a broom handle waved through the photo eye beam, which must do the same. A door that sat closed all winter deserves a look at the springs, rollers and bottom seal before the season starts.

The beach towns license rentals and limit work days. Lewes requires a city rental license for every rental, and a short-term rental needs a local contact who can reach the house within two hours. Rehoboth Beach renews rental licenses every year and expects rentals to be in good repair, and Dewey Beach and Bethany Beach license any home rented at any time of year. Rehoboth bars construction on Saturdays from May 1 to October 31 and Fenwick Island from May 15 to September 15, so plan door work for a weekday between bookings.

Distance from the surf, flood mapping and local rules change from town to town. Blue Hen works in all eight from our office in Dover.

• Lewes: The city names Delaware Bay, the Lewes and Rehoboth Canal and Canary Creek as flood sources, and the Historic Preservation Architectural Review Commission (HPARC) reviews street-visible exterior changes in the Historic District.
• Rehoboth Beach: The city's mapped floodplain runs around Silver Lake and from the ocean to beyond the boardwalk.
• Dewey Beach: About two blocks wide between the ocean and Rehoboth Bay, with most of town in a Special Flood Hazard Area and every lot well inside FEMA's 3,000-foot band.
• Bethany Beach: About 80 percent of town lies in a Special Flood Hazard Area, and oceanfront lots can fall in a VE zone.
• Ocean View: About a mile west of the Atlantic, beyond the 3,000-foot band, with the Assawoman Canal and Whites Creek nearby; town permits call for HOA approval where it applies.
• Millville: West of Ocean View and outside the 3,000-foot strip, where steel doors with galvanized hardware are a sensible fit; permit applications include an HOA letter in HOA communities.
• Fenwick Island: A narrow spit between the ocean and Little Assawoman Bay that lies entirely in a Special Flood Hazard Area, where the town plan says flooding across much of the bay side seems to happen at least once a year.
• Selbyville: About 33 feet above sea level, against about 7 feet for Fenwick Island eight miles east, and well inland of the 3,000-foot band.