Most wood fences in this parish don't fail at the pickets. They fail two inches above and two inches below the dirt line, where the post stays wet, and everything above it goes along for the ride. If your gate has started dragging, if a section leans after a windy week, or if you can push a screwdriver into the base of a post, the fence is telling you the posts are done — and patching pickets onto dying posts just buys a season.
Ground water sits high here. A post hole dug in the morning can have water in the bottom by the time the concrete comes out of the bag, and that changes how the job has to be done. Wood that's rated for above-ground use will not survive buried in saturated clay — ground-contact treated pine, or a steel post sleeved inside a wood jacket, is what holds up. Cypress and cedar are beautiful for pickets and rails and they weather to a soft grey, but they still want a post that can live underwater half the year. Termites are the second half of the equation: any untreated wood touching soil is an invitation, which is why pickets should stop short of the dirt rather than resting on it, and why trim boards and kickboards need the same treatment rating as the posts.
Wind is the third factor. A six-foot privacy fence is a solid sail, and in open yards in Chalmette and out toward Meraux it takes the full push. That's handled with post depth, post spacing, and how the rails attach — not with heavier pickets. Shadowbox and board-on-board styles let some air through and ride out gusts better than a tight stockade, which is worth weighing if your run faces open ground or a canal.
A proper wood fencing job starts with the line, not the lumber. Property pins get located or a survey gets referenced, utility locates get called in before anything is dug, and the run gets strung so you know where posts land before a hole exists. Old fence comes out, including the old concrete footings — leaving them in the ground forces new posts off-line and is one of the most common shortcuts. Holes are dug to depth and belled or widened at the bottom where soil is soft. Posts are set plumb, braced, and left to cure before any weight goes on them. Rails go on next, then pickets, then gates last, because gates need to be built to the opening as it actually ended up, not as it was drawn.
Details that separate a ten-year fence from a three-year one: concrete crowned above grade so water sheds away from the post instead of pooling in a cup around it, hot-dipped galvanized or stainless fasteners so you don't get black rust streaks bleeding down new wood, screws rather than nails at every gate joint, and a diagonal brace or tension cable on any gate wider than about four feet. Driveway gates and double gates need heavier hinges, a drop rod, and often a steel-framed leaf — a wide gate built like a fence panel will sag within a year no matter how good the wood is.
Linear footage and height are the obvious drivers. After that it's post material, the style you pick, the number and width of gates, whether old fence has to come out and get hauled away, and access. A back yard reachable only through a narrow side gate means every post, bag of concrete and bundle of pickets goes by hand, and that's labor. Sloped or stepped runs, tree roots, and existing slabs all add time. Shared lines are worth sorting before work starts — talk to the neighbor about who pays and which side the rails face.
Ask what treatment rating the posts carry, how deep they're going, what the post spacing is, and how the gates will be braced. Ask whether old footings are being removed. Ask when you can stain: fresh treated pine needs to dry out before it will take a finish, and sealing it wet traps moisture in the board. On the day, clear the fence line, point out sprinkler heads and septic or drain lines, and keep pets inside — the yard is open while posts cure. The same questions apply whether the fence is going up in Arabi, Gretna, or around the corner from here.