1. What is Rafter Length Calculation?

The rafter length calculation determines the length of roof rafters based on the roof span and rise. This is essential for proper roof construction and material estimation.

2. How Does the Calculator Work?

The calculator uses the Pythagorean theorem:

Where:

• \( Span \) — Total horizontal distance between the outer edges of the roof
• \( Rise \) — Vertical height from the top of the wall to the roof peak

Explanation: The formula calculates the hypotenuse of a right triangle where half the span and the rise form the two perpendicular sides.

3. Importance of Accurate Rafter Length

Details: Precise rafter length calculation ensures proper roof construction, prevents material waste, and maintains structural integrity.

4. Using the Calculator

Tips: Enter span and rise in meters. Both values must be positive numbers. The calculator provides the rafter length in meters.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between span and run?
A: Span is the total horizontal distance between walls, while run is half the span (distance from wall to roof center).

Q2: How do I measure rise?
A: Rise is the vertical distance from the top of the wall to the highest point of the roof.

Q3: Does this work for all roof types?
A: This calculation works for simple gable roofs. Complex roof designs may require additional calculations.

Q4: Should I add extra length for overhangs?
A: Yes, the calculated length is the basic rafter length. Add additional length for any desired overhangs.

Q5: How precise should my measurements be?
A: For construction purposes, measure to the nearest centimeter (0.01 meter) for best results.