1. What is a DDA Ramp Gradient Calculator?

Definition: This calculator determines the gradient of a ramp according to Disability Discrimination Act (DDA) standards, based on the height and length of the ramp.

Purpose: It helps architects, builders, and accessibility consultants ensure ramps meet accessibility requirements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( G \) — Gradient (unitless ratio)
• \( H \) — Height difference (meters)
• \( L \) — Length of ramp (meters)

Explanation: The height is divided by the length to determine the ramp's steepness. DDA typically requires gradients ≤ 1:12 (8.33%).

3. Importance of Ramp Gradient Calculation

Details: Proper gradient calculation ensures wheelchair accessibility, safety, and compliance with disability access regulations.

4. Using the Calculator

Tips: Enter the height difference in meters and the ramp length in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the maximum DDA compliant gradient?
A: The maximum recommended gradient is 1:12 (8.33%) for wheelchair access, though 1:15 (6.67%) is preferred.

Q2: How do I convert gradient to percentage?
A: Multiply the gradient by 100. For example, 0.0833 × 100 = 8.33%.

Q3: What if my calculated gradient exceeds DDA standards?
A: You'll need to increase the ramp length or consider adding intermediate landings to break up the slope.

Q4: Does this account for ramp landings?
A: No, landings should be provided every 10m of ramp length or where direction changes occur.

Q5: What about minimum ramp width requirements?
A: DDA requires minimum 1200mm width for straight ramps and 1500mm width for turning ramps.