木製フェンス計算ツール

A wood fence estimate breaks into three independent counts run against the same fence length: posts at the spacing you choose, rails per section sized to height, and pickets sized to board width and gap. This calculator runs all three together so changing one input, such as moving from a 6 foot to an 8 foot fence, updates the suggested rail count and post size at the same time. Species sets price and expected service life, not the arithmetic: pine, cedar and redwood pickets of the same width and gap all produce the same picket count, which is why this page defaults to cedar but leaves the material open. For a per-board count on its own, the fence picket calculator isolates that one step and is useful for double-checking a lumber order against what this page returns.

Style changes the picket formula more than species does. A butted privacy fence runs boards with no gap, so the count is simply the run divided by board width. Board-on-board overlaps each picket over its neighbor, which tightens the effective spacing below the board's own width and raises the count by roughly a fifth to a third over a butted layout covering the same run. A classic picket style with a visible gap between boards needs fewer pickets than either, since the gap widens the pitch. Getting the style right before ordering lumber matters more than getting the species right, because the style is what drives the picket quantity on a long run, and a mis-set gap field is one of the more common ways an otherwise careful material take-off comes out wrong.

Posts are the other half of the take-off, and they follow the run length and corner count rather than the picket style. Post spacing of 6 to 8 feet on center is standard for a wood privacy fence, tightening toward 6 feet in windy areas or stepping up to a 6x6 post at 8 feet of height or beyond. Once post count and hole size are set, the fence post concrete calculator converts that into bags of mix, and the fence post depth calculator checks that your planned depth, commonly about a third of the post's total length, clears the local frost line where the ground freezes. Skipping either step tends to show up later as a wobbly post or a short concrete order on delivery day, both of which cost more to fix after the fact than to plan for up front.

Once the bill of materials is set, the fence cost calculator turns post, rail and picket counts into a dollar total using your own local unit prices rather than a generic national average. For the install sequence itself, from layout string lines to setting the first corner post, the wood fence installation guide and the how to install a wood privacy fence post walk through the order of operations, while how many rails does a fence need and how deep should a 6 foot fence post be cover two of the most commonly second-guessed numbers on a wood fence job. The fence materials guide compares species side by side for anyone still deciding before running the numbers here, and the full wood fence calculators hub links every style-specific version of this page.

Corner and end posts carry more load than a line post in the middle of a run, since they anchor the pull of the rails rather than simply supporting a span on each side, which is part of why some installers oversize corner posts even when the rest of the run uses a smaller size. Gates subtract their width from the run before pickets and rails are counted and add their own post pair plus hardware, a step this calculator already applies automatically rather than leaving it as a manual correction. On a property with multiple corners or an irregular boundary, it is worth running the post count once with the actual corner layout rather than treating the whole property line as one straight run, since a boundary with several turns needs more posts than the same total footage walked in a straight line would.

Lumber moisture content affects wood fencing differently by species: pressure-treated boards arrive wet and shrink as they dry outdoors, which is why they are typically installed tightly butted, while kiln-dried cedar and redwood are closer to their final dimension at install time. A waste allowance, commonly 10 percent for pickets and rails, covers cut ends at corners and gates plus the occasional warped, split or badly knotted board that gets rejected on site, and a longer run with more corners generally warrants a higher allowance than a short straight stretch. None of this changes the core formulas, but it is the difference between a material order that covers the job on the first delivery and one that comes up short midway through installation.