1. What is an ADA Wheelchair Ramp Slope Calculator?

Definition: This calculator determines the slope of a wheelchair ramp based on the rise and run measurements, and checks ADA compliance.

Purpose: It helps architects, builders, and homeowners design wheelchair-accessible ramps that meet ADA requirements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• Rise — Vertical height change (inches)
• Run — Horizontal length (inches)
• Slope Ratio — Expressed as 1:X (e.g., 1:12)
• Slope Percentage — (Rise/Run) × 100

ADA Compliance: The maximum allowable slope is 1:12 (8.33%) for wheelchair ramps.

3. Importance of Proper Ramp Slope

Details: Correct slope ensures safe, accessible ramps that meet legal requirements and provide comfortable use for wheelchair users.

4. Using the Calculator

Tips: Enter the rise and run in inches. The calculator will show the slope ratio, percentage, and ADA compliance status.

5. Frequently Asked Questions (FAQ)

Q1: What's the maximum ADA-compliant slope?
A: 1:12 slope (8.33%) is the maximum for wheelchair ramps. Steeper slopes may require handrails or are not permitted.

Q2: How do I measure rise and run?
A: Rise is the vertical height from ground to landing. Run is the horizontal length of the ramp.

Q3: What if my slope isn't ADA compliant?
A: Increase the run length or decrease the rise to achieve a gentler slope, or consider adding intermediate landings.

Q4: Are there exceptions to the 1:12 rule?
A: Existing sites may allow 1:10 (10%) for short rises, and 1:8 (12.5%) for very short rises (≤3 inches).

Q5: Does this calculator account for landings?
A: No, remember to include level landings at least 60 inches long at the top, bottom, and where direction changes.