1. What is Roof Pitch?

Roof pitch is the steepness of a roof expressed as a ratio of vertical rise to horizontal run, or as an angle in degrees. In the UK, roof pitch is typically expressed as a ratio (e.g., 4:12) or in degrees.

2. How Does the Calculator Work?

The calculator uses the roof pitch formula:

Where:

• Rise — Vertical height (meters)
• Run — Horizontal distance (meters)
• arctan — Inverse tangent function

Explanation: The formula calculates the angle of the roof based on the vertical rise and horizontal run measurements.

3. Importance of Roof Pitch Calculation

Details: Accurate roof pitch calculation is crucial for proper roofing material selection, drainage planning, structural integrity, and compliance with building regulations.

4. Using the Calculator

Tips: Enter rise and run measurements in meters. Both values must be positive numbers. The calculator will provide results in degrees, ratio, and radians.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical roof pitch in the UK?
A: Most UK roofs have a pitch between 30-50 degrees, with 35-40 degrees being very common for traditional housing.

Q2: How is roof pitch expressed in the UK building industry?
A: Roof pitch is typically expressed as a ratio (e.g., 4:12) meaning 4 units of vertical rise for every 12 units of horizontal run.

Q3: Why is roof pitch important?
A: Roof pitch affects water drainage, snow load capacity, suitable roofing materials, attic space, and overall aesthetic appearance.

Q4: What's the minimum roof pitch for different roofing materials?
A: Slate and tile roofs typically require at least 20-30 degrees, while felt flat roofs can work with as little as 1-10 degrees pitch.

Q5: How do I measure rise and run for an existing roof?
A: For existing structures, you can measure the total height from eaves to ridge (rise) and half the building width (run), or use specialized tools like a pitch gauge.