1. What is Slope Calculation?

Slope calculation measures the steepness or incline of a surface, expressed as the ratio of vertical change (rise) to horizontal change (run). In this calculator, rise is measured in inches and run in feet.

2. How Does the Calculator Work?

The calculator uses the slope equation:

Where:

• \( m \) — Slope (unitless)
• \( rise \) — Vertical change in inches
• \( run \) — Horizontal change in feet
• \( 12 \) — Conversion factor (inches per foot)

Explanation: The formula converts run from feet to inches (by multiplying by 12) to maintain consistent units with rise, then calculates the slope ratio.

3. Importance of Slope Calculation

Details: Slope calculation is essential in construction, landscaping, road design, and drainage planning. It helps ensure proper grading for water runoff, accessibility compliance, and structural stability.

4. Using the Calculator

Tips: Enter rise in inches and run in feet. Both values must be positive numbers, with run greater than zero. The result is a unitless slope value.

5. Frequently Asked Questions (FAQ)

Q1: Why convert run from feet to inches?
A: To maintain consistent units - both numerator and denominator must be in the same units for accurate slope calculation.

Q2: What does the slope value represent?
A: The slope value represents the ratio of vertical change to horizontal change. For example, a slope of 0.0833 means 1 inch of rise per 12 inches (1 foot) of run.

Q3: What is a typical slope for drainage?
A: For proper drainage, a minimum slope of 1-2% (0.01-0.02) is typically recommended, which equals approximately 0.12-0.24 inches per foot.

Q4: How is slope expressed as a percentage?
A: Slope percentage = slope × 100%. For example, a slope of 0.05 equals a 5% grade.

Q5: What's the maximum slope for wheelchair accessibility?
A: ADA guidelines typically require slopes no greater than 1:12 (8.33%) for ramps, which equals a slope of approximately 0.0833.