Pipe fence posts run 8 to 10 feet apart. Wire fence t-posts run 8 to 12 feet with braced, concreted corner assemblies doing the real work. Privacy fence posts run 6 to 8 feet to carry wind load. Gate and corner posts go deeper and heavier than the line, always.
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Spacing rules follow what the fence resists. Welded pipe fence carries loads through its rails, so posts at 8 to 10 feet keep rail spans stiff enough that a leaning animal meets steel, not spring; closer spacing at gates and working pens where pressure concentrates is normal. Wire fence works by tension, so its line posts (t-posts at 8 to 12 feet) mostly hold wire height and spacing, while the corner and end assemblies (braced H-frames, set in concrete) anchor the tension of the whole run; that is why wire fence quality is judged at its corners, and why a fence with 12-foot spacing and proper braces outlasts one with 8-foot spacing and lazy corners. Privacy fence is a sail: a 6-foot cedar panel takes real wind load, so posts run 6 to 8 feet apart, set deep, and the north-wind side of an exposed lot argues for the tighter number and steel posts over wood. Depth rules are as important as spacing: the working rule is a third of the post's height in the ground (a 6-foot privacy fence on 2-plus feet of buried post), gate and corner posts deeper and bigger because they carry cantilever and tension loads the line never sees, and concrete around anything that carries a gate. One local wrinkle: on the Blackland side, expansive clay works shallow posts loose over wet-dry cycles, which is one more argument for depth and concrete at every structural post. For outer limits, the Texas NRCS fence specification behind cost-shared conservation fences allows barbed and woven wire line posts up to 20 feet apart without stays or 30 feet with them, sets anchor posts at least 3 feet deep with more depth in sandy or wet ground, requires a brace assembly wherever a fence starts, stops, or turns 20 degrees or more, and calls for double H-braces on runs over 660 feet between anchors. Working fences here run well inside those ceilings, which is why the spacing above is tighter. The pipe versus wire FAQ covers which family fits your animals, and fence lines on the sandy ground around Whitesboro or the clay around Bonham are priced post by post in a written scope. And before any auger turns: 811 utility locates, every time.