1. What is Rainfall Volume Calculation?

Rainfall volume calculation estimates the amount of water collected from a roof surface during rainfall. It's useful for rainwater harvesting system design and stormwater management planning.

2. How Does the Calculator Work?

The calculator uses the rainfall volume formula:

Where:

• \( Roof Area \) — Surface area of the roof (m²)
• \( Rainfall \) — Amount of rainfall (m)
• \( 0.95 \) — Collection efficiency coefficient for typical roofs

Explanation: The formula accounts for water loss due to evaporation, splashing, and initial wetting of the roof surface.

3. Importance of Rainfall Volume Calculation

Details: Accurate rainfall volume calculation is essential for designing adequate rainwater storage systems, managing stormwater runoff, and assessing water harvesting potential.

4. Using the Calculator

Tips: Enter roof area in square meters and rainfall in meters. Both values must be positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why use 0.95 as the coefficient?
A: The 0.95 coefficient accounts for typical water losses from evaporation, splashing, and initial wetting of the roof surface during rainfall events.

Q2: How accurate is this calculation?
A: The calculation provides a good estimate for planning purposes, but actual collection may vary based on roof material, slope, and rainfall intensity.

Q3: Can this be used for any roof type?
A: While the 0.95 coefficient works for most typical roofs, highly absorbent or uneven surfaces may require adjustment of the efficiency coefficient.

Q4: What units should I use for rainfall?
A: Rainfall should be entered in meters. Remember that 1 mm of rainfall = 0.001 m.

Q5: How can I use this for rainwater harvesting?
A: The calculated volume helps determine appropriate storage tank size and potential water savings for residential or commercial rainwater harvesting systems.