1 20 Slope Calculator With 3

1:20 Slope Calculation:

\[ Slope = \frac{Rise}{Run} = \frac{1}{20} \]

Average Slope:

1:20 Slope Target:

Deviation from Target:

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1. What is a 1:20 Slope?

A 1:20 slope means that for every 20 units of horizontal distance (run), the vertical rise is 1 unit. This is equivalent to a 5% grade or an angle of approximately 2.86 degrees. It's commonly used in construction, landscaping, and engineering for drainage, ramps, and other inclined surfaces.

2. How Does the Calculator Work?

The calculator uses three coordinate points to determine the average slope:

\[ Slope = \frac{Rise}{Run} = \frac{y_2 - y_1}{x_2 - x_1} \]

The calculator calculates slopes between all three point combinations and averages them:

Slope between Point 1 and Point 2
Slope between Point 1 and Point 3
Slope between Point 2 and Point 3

Explanation: Using three points provides a more accurate measurement by averaging multiple slope calculations, reducing the impact of measurement errors in any single point.

3. Importance of Slope Calculation

Details: Accurate slope calculation is crucial for proper drainage, accessibility compliance, structural integrity, and safety in construction projects. A 1:20 slope is often the minimum requirement for wheelchair ramps and surface drainage.

4. Using the Calculator

Tips: Enter the coordinates of three points along the slope. For best results, choose points that are spread out along the slope rather than clustered together. The calculator will determine the average slope and compare it to the 1:20 target slope.

5. Frequently Asked Questions (FAQ)

Q1: Why use three points instead of two?
A: Using three points and averaging the slopes provides a more accurate measurement that is less affected by measurement errors in any single point.

Q2: What units should I use for coordinates?
A: You can use any consistent units (feet, meters, inches, etc.) as long as you use the same units for all measurements.

Q3: How accurate is this calculation?
A: The accuracy depends on the precision of your measurements. The calculator provides results with 4 decimal places for slope and 2 decimal places for percentage deviation.

Q4: What is an acceptable deviation from 1:20 slope?
A: This depends on the application. For ADA wheelchair ramps, typically no more than 1-2% deviation is acceptable. For drainage, slightly larger deviations may be tolerable.

Q5: Can I use this for steeper slopes?
A: Yes, the calculator works for any slope, though it's specifically designed to compare against a 1:20 slope target.