Crush Run Aggregate Calculator
Use this calculator to estimate the amount of crush run (also known as crusher run, 21A, or 21AA) aggregate you'll need for your project. Crush run is a versatile material often used as a stable base for driveways, patios, walkways, and foundations due to its excellent compaction properties.
(Typical range: 2400-2800 lbs/cubic yard)
Understanding Crush Run Aggregate
Crush run is a specific type of aggregate material that consists of crushed stone and stone dust. The mixture of different particle sizes allows it to interlock and compact very tightly, creating a strong and stable base. This makes it ideal for a variety of construction and landscaping applications where a solid, well-drained foundation is required.
Common Uses for Crush Run
- Driveways and Parking Pads: Provides a durable and stable base that can withstand vehicle traffic.
- Patios and Walkways: Creates a firm foundation for pavers, flagstones, or concrete slabs.
- Shed and Building Foundations: Offers a level and compact base to support structures.
- Retaining Wall Backfill: Improves drainage and stability behind retaining walls.
- Road Base: Used as a sub-base layer in road construction.
Why Accurate Calculation Matters
Estimating the correct amount of crush run is crucial for several reasons:
- Cost Efficiency: Ordering too much leads to wasted material and disposal costs. Ordering too little results in project delays and additional delivery fees.
- Project Success: An insufficient base can compromise the stability and longevity of your project, leading to settling, cracking, or uneven surfaces.
- Time Management: Having the right amount on hand prevents interruptions and keeps your project on schedule.
How the Calculator Works
Our Crush Run Calculator uses a simple formula to determine the volume and weight of material needed:
- Area Calculation: It first calculates the total area of your project by multiplying the Area Length by the Area Width.
- Volume Calculation: This area is then multiplied by the Desired Layer Depth (converted from inches to feet) to get the total volume in cubic feet.
- Cubic Yards Conversion: Since crush run is often sold by the cubic yard, the cubic feet volume is divided by 27 (as there are 27 cubic feet in 1 cubic yard).
- Weight Calculation: Finally, the volume in cubic yards is multiplied by the Crush Run Density (in pounds per cubic yard) to determine the total weight in pounds, which is then converted to tons.
Factors to Consider
- Compaction: Crush run compacts significantly. While the calculator provides a theoretical volume, it's often recommended to add 10-15% extra material to account for compaction and minor waste.
- Irregular Shapes: For areas that aren't perfectly rectangular, try to break them down into smaller, measurable rectangles or use an average length and width.
- Slope: If your area has a significant slope, the depth will vary. Consider using an average depth or calculating sections separately.
- Density Variation: The density of crush run can vary slightly depending on the type of stone and local quarry. The default value of 2700 lbs/cubic yard is a good average, but you can adjust it if you have specific information from your supplier.
Example Calculation
Let's say you're building a driveway that is 50 feet long and 10 feet wide, and you want a 6-inch deep crush run base. Using a typical density of 2700 lbs/cubic yard:
- Length: 50 feet
- Width: 10 feet
- Depth: 6 inches = 0.5 feet
- Density: 2700 lbs/cubic yard
The calculator would perform the following steps:
- Volume in Cubic Feet: 50 ft * 10 ft * 0.5 ft = 250 cubic feet
- Volume in Cubic Yards: 250 cubic feet / 27 cubic feet/yard = 9.26 cubic yards (approximately)
- Weight in Pounds: 9.26 cubic yards * 2700 lbs/cubic yard = 25002 lbs
- Weight in Tons: 25002 lbs / 2000 lbs/ton = 12.50 tons (approximately)
Therefore, you would need approximately 9.26 cubic yards or 12.50 tons of crush run for this project.