Rafter pairs

Calculate Rafter pairs instantly with the exact formula and a worked example. Free online calculator — no signup.

Rafter pairs

House lengthm
Widthm
Rafter spacingm
Rafter pairs
18
Calculate Rafter pairs instantly with the exact formula and a worked example. Free online calculator — no signup.

More about: Rafter pairs

What it calculates

The “Rafter pairs” calculator computes Rafter pairs from 3 parameters: house length (m), width (m), rafter spacing (m).

Used in design, material estimation, and structural calculations.

Example calculation

With parameters House length = 10 m, Width = 8 m, Rafter spacing = 0.6 m the result is 18.

How to use

  1. Enter the parameter values — every field above is adjustable with a slider.
  2. The result and related metrics are calculated automatically as you type.
  3. Use the additional metrics shown (if any) where needed.
  4. Copy the result or bookmark the page.

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