寄棟屋根計算機

共有リンク

はじめに

Hip Roof Calculator — Hip rafter length for a hip roof. Enter Rise (ft), Run (ft) to get an instant, accurate result.

計算式

Hip rafter length = √(diagonal run² + rise²), where diagonal run = run × √2 for a standard 45-degree hip line — extending the Pythagorean rafter-length relationship into three dimensions.

ステップごとの説明

Enter the Rise (ft).
Enter the Run (ft).
Click Calculate to see your result instantly.

実例

Example: With Rise (ft) = 6, Run (ft) = 12, the Hip Roof Calculator gives Hip Rafter Length Ft: 18, Diagonal Run Ft: 16.9706.

よくある質問

Why multiply run by √2?

A hip rafter runs diagonally across the roof at 45 degrees to the common rafters, so its horizontal projection is the run multiplied by √2 (the diagonal of a square).

Does this assume a square hip roof footprint?

Yes, the 45-degree diagonal assumption applies to a standard hip roof with equal slopes; irregular or non-45-degree hips require a different calculation.

What inputs does the Hip Roof Calculator need?

You'll need to provide: Rise (ft), Run (ft). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.

How accurate is the Hip Roof Calculator?

The Hip Roof Calculator applies the formula exactly as calculated — Hip rafter length = √(diagonal run² + rise²), where diagonal run = run × √2 for a standard 45-degree hip line — extending the Pythagorean rafter-length relationship into three dimensions. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.

Is the Hip Roof Calculator free to use?

Yes, the Hip Roof Calculator is completely free, requires no signup, and runs instantly in your browser.