1. What Is Flat Roof Gradient?

Flat roof gradient refers to the slope or incline of a flat roof, calculated as the ratio of vertical rise to horizontal run. It determines how effectively water drains from the roof surface.

2. How Does The Calculator Work?

The calculator uses the gradient formula:

Where:

• \( rise \) — Vertical height difference (meters)
• \( run \) — Horizontal distance (meters)

Explanation: The formula calculates the slope ratio by dividing the vertical rise by the horizontal run, resulting in a unitless gradient value.

3. Importance Of Gradient Calculation

Details: Proper gradient calculation is essential for ensuring adequate water drainage, preventing ponding water, and meeting building code requirements for flat roof construction.

4. Using The Calculator

Tips: Enter both rise and run values in meters. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the minimum gradient required for flat roofs?
A: Most building codes require a minimum gradient of 1:80 (1.25%) for proper water drainage, though specific requirements may vary by location.

Q2: How is gradient different from slope percentage?
A: Gradient is expressed as a ratio (e.g., 1:40), while slope percentage is the rise divided by run multiplied by 100 (e.g., 2.5%).

Q3: Can I use different units for rise and run?
A: The calculator uses meters, but you can use any consistent unit as long as both rise and run are in the same unit of measurement.

Q4: What happens if the gradient is too flat?
A: Insufficient gradient can lead to water pooling, increased leakage risk, and potential structural damage over time.

Q5: How does gradient affect roofing material choice?
A: Different roofing materials have specific minimum gradient requirements. Lower gradients may require specialized waterproofing systems.