1. What is a 20mm Gravel Calculator?

Definition: This calculator estimates the volume of 20mm gravel needed based on the area to be covered and the desired depth.

Purpose: It helps construction professionals and DIYers determine how much 20mm gravel is required for projects like driveways, pathways, or drainage systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( V \) — Volume of gravel (cubic yards)
• \( A \) — Area to be covered (square feet)
• \( D \) — Depth of gravel layer (feet)
• \( 27 \) — Conversion factor (cubic feet per cubic yard)

Explanation: The area multiplied by depth gives cubic feet, which is then converted to cubic yards by dividing by 27.

3. Importance of 20mm Gravel Volume Calculation

Details: Proper gravel volume estimation ensures adequate coverage, proper drainage, and cost-effective material purchasing. 20mm gravel is ideal for drainage applications and as a base material.

4. Using the Calculator

Tips: Enter the area in square feet and desired depth in feet. All values must be > 0. For typical applications, a depth of 0.25-0.5 feet (3-6 inches) is common.

5. Frequently Asked Questions (FAQ)

Q1: Why use 20mm gravel specifically?
A: 20mm gravel provides excellent drainage while being stable enough for walking or light vehicle traffic.

Q2: How do I measure the area?
A: Multiply length by width for rectangular areas. For irregular shapes, break into smaller rectangles and sum the areas.

Q3: What depth should I use?
A: For driveways, use 4-6 inches. For pathways, 2-3 inches is often sufficient. For drainage, consult project specifications.

Q4: Does this include compaction?
A: No, consider adding 10-20% to the calculated volume to account for compaction if needed.

Q5: How many bags will I need?
A: Bulk gravel is typically sold by cubic yard. One cubic yard covers about 100 sq ft at 3-inch depth.

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