フェンス門計算ツール
歩行用の門でも両開きの通行口でも、開口部、それを支える支柱、そして門に必要な金物をまとめて計画します。
Fence Calculator
仕様を入力してください。結果はリアルタイムに更新され、式も表示されます。
概要
門は、朝夕に2回動かさなければならないフェンスの一部です。どうせ開閉の荷重を受けるので、開口部、門の幅、そしてヒンジの荷重を支える支柱は、フェンスの延線を計画した後に決めるのではなく、一まとまりで計画します。
歩行用の門は3から4フィート、通行用は10から12フィート(多くは両開き)が一般的で、どの門にもヒンジ側とラッチ側に正しい大きさの支柱が要ります。中間の支柱には決してかからない荷重を、この2本が受け持つからです。
前提条件
- Walk gates default to a common 4 foot opening and drive gates to a wider double configuration, both editable.
- A gate opening removes that span of run from the fence material take-off.
- The opening is the clear space between posts; the gate panel is build slightly larger to overlap that opening.
よくある間違い
- フェンスの延長に合わせた普通の支柱に門を吊るすこと。ヒンジ側とラッチ側の支柱には、揺れの荷重に耐える太い材が必要です。
- 開口部を測った幅と同じ幅の門を注文すること。ヒンジとラッチが揺れる余裕が残りません。
- 広い通行口には門1枚ではなく、両開きか強度の高い枠が必要なことを忘れること。
フェンス計算の式
計算機が走らせる同じ数式を、平たく。ブラックボックスはありません。
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スパン数
sections = max(ceil(effective run / post spacing), 1)
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柱数
posts = (sections + 1) along the run, minus named corner and end posts already placed, plus 2 gate posts per gate
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有効延長
effective run = total length - sum of gate widths
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横木数
total rails = sections x rails per section
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ピケット数
pickets = ceil(run in inches / (picket width + gap)); total = ceil(raw x (1 + waste %))
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Board-on-Boardのピッチ
pitch = picket width - 1 inch overlap
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パネル数
full panels = floor(run / panel width); add 1 cut panel if the remainder is over 0.01 ft; total = ceil(raw x (1 + waste %))
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コンクリート量
per-hole = pi x (diameter / 2)^2 x depth; total = per-hole x posts; bags = ceil(total / bag yield)
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勾配調整長
slope run = effective run / cos(atan(slope % / 100)); shown alongside, counts use the flat run
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費用
materials = (posts x post price + rails x rail price + infill x unit price + 60 lb bags x bag price) x regional multiplier; labor = effective run x labor per ft x terrain multiplier x regional multiplier; installed total = materials + gate hardware + removal + permit + labor
計算機が示す数字はすべて、これらの式にあなたの入力を当てた結果です。
次のステップ
関連する計算ツール
関連する読み物
詳細なガイド
購入ガイド
A fence gate calculator earns its keep by treating the gate opening as its own build decision instead of an afterthought tacked onto the fence run. The opening width, the posts that carry the hinge and latch loads, and the hardware that holds the leaf all have to agree with each other before a single post hole gets dug. Get the opening wrong and the gate panel either binds on the posts or leaves a gap wide enough for a dog to squeeze through. Get the post sizing wrong and the gate sags within a season, no matter how square and well built the panel was when it left the shop or came off the workbench. This calculator starts from the opening you need and works outward to the post and hardware decisions that make that opening function as a door, not just a hole in the fence line. Keyword searches for a fence gate calculator usually come from someone standing in the yard trying to decide between a single leaf and a double leaf, and that decision depends mostly on the opening width and how the gate will actually be used, not on preference alone.
Walk gates and drive gates are different problems even though they share the same basic math. A walk gate at 3 to 4 feet wide carries light, occasional traffic and can run on a single leaf without much drama. A drive opening at 10 to 12 feet is a different animal: a single leaf that wide gets heavy enough to rack its own frame and torque the hinge post out of plumb within a year or two, which is why wide openings are almost always split into two leaves that meet in the middle. If you are sizing a drive opening, the double gate calculator handles the per-leaf width and the center meeting gap directly, since that math is different enough from a single swinging leaf to deserve its own tool. Once you know how wide the opening needs to be, the gate width calculator converts that clear opening into the actual panel dimension you order or build, accounting for the small clearance gap a leaf needs on each side so it swings without dragging.
The posts on either side of a gate are not the same as the line posts carrying the rest of the fence, and this is the detail that gets skipped most often on a DIY build. A line post only resists lateral push from wind and the occasional lean; a hinge post resists a constant cantilevered load every single time the gate is opened and left standing, plus the repeated shock of it being slammed shut by hand. That is why gate and latch posts are commonly upsized, set deeper, and set in more concrete than the rest of the run, a point covered in more detail in the gate hardware and framing guide. The fence post calculator and post concrete calculator are useful once you have the gate post count settled, since the concrete volume for a deeper, wider gate post hole is noticeably more than a standard line post takes, and running out of mix halfway through a gate post pour is a common and avoidable delay.
A gate also changes two numbers in the material take-off that are easy to miss. First, the gate opening removes that linear span from the fence panel or picket count, since nothing but the gate itself fills that gap. Second, the two gate posts still count toward the post total even though no fence panel attaches to their outer face the way it does on a line post. Getting that subtraction backward is the difference between finishing a job with a pile of spare pickets or coming up short a full section near the end. The how many posts for a fence guide walks through that count in more detail, and how to brace a sagging fence gate is worth reading before the build if the opening is wide or the material is heavy, since a diagonal brace installed in the wrong direction at the start does nothing to stop the long-term sag it is meant to prevent. For a full cost picture once the opening, posts and hardware are settled, the fence cost calculator rolls the gate into the rest of the fence budget, and the broader set of gate tools and material calculators live together under the gate calculators category alongside the privacy fence options at the privacy fence calculator for anyone building the gate into a full privacy run and wanting consistent material and framing choices on both sides of the opening, which keeps the fence materials guide at fence materials guide as a useful cross reference for matching the gate frame material to the fence panels it sits between.
よくある質問
歩行用の門はどのくらいの幅にすべきですか。
歩行用の開口部は3から4フィートが一般的で、4フィートなら一輪車や芝刈り機が楽に通せます。開口幅に合わせた門を、脇の余裕を取って作れば自由に揺れます。
両開きの通行口はどのくらい必要ですか。
通行用の開口部は10から12フィートが一般的で、両開きとして作られます。中央で合わさる2枚の扉にするのは、12フィートの木製扉1枚では重くなり、ヒンジ側の支柱に負担が残るからです。
門にはどんな支柱が必要ですか。
門の支柱とラッチ側の支柱は、中間の支柱より太くします。木製なら一般に4x6以上を選び、より深く、より多くのコンクリートで据えます。揺れる門は、支柱に普通のフェンスとは違う力矩をかけるからです。
門の開口部と門のパネル幅は同じですか。
違います。パネルは隙間を覆うため、開口部より少し大きく作ります。通常は片側に数インチの余裕を加えます。開口幅に12を掛け、合計数インチの余裕を引くとパネル幅になります。門幅計算ツールがその換算を行います。
門が揺れるのにどれくらい余裕が必要ですか。
扉が地面を擦らないようにパネルは片側に少しの余裕を取ります。片側1インチ回復が目安です。パネル寸法に換算した値が必要なら、門幅計算ツールにあります。
門1組の金物は何からなりますか。
基本はヒンジ2個(またはヒンジストラップの組)、ラッチ、ハンドルです。大きな扉には重い車輪や投げ掛けラッチを付けます。毎日の開閉という用途で重要な荷重定格は、門の金物ガイドで扱っています。
門の支柱にも他の支柱と同じコンクリートが必要ですか。
はい、しかもより多く必要です。門の支柱はヒンジの荷重が集中するので、より深い、より太い穴に、余分なコンクリートを入れて据えます。門の支柱に合わせて穴を広げるあとは、支柱のコンクリート計算ツールが袋数を出してくれます。
門はフェンスの延長から差し引きますか。
差し引くべきです。門の部分はパネルで埋まらないので、資材の手計算では門の開口部の分だけ延長を短くします。ただし門の支柱2本は支柱の数に残します。この引き算を間違えると、工事の終わりに板が余るか足りなくなるかが分かれます。