#4 Trap Rock (1 - 3")

#4 Trap Rock (1 - 3"): Technical Overview and Practical Information

#4 Trap Rock, also known as 1 - 3" crushed stone, is a dense, angular aggregate sourced from hard, volcanic rock such as basalt or diabase. The stone pieces range from 1 to 3 inches (25 to 75 mm) in size. This product is not a common base for light-duty surfaces. It is specifically used for heavy-duty base layers. The material is too large to walk on comfortably and is not suitable for driving directly on top as a finished surface. Its angular shape and rough texture allow the pieces to interlock, forming a stable, load-bearing foundation. This makes #4 Trap Rock ideal for supporting roads, industrial pads, and railroad ballast where high compressive strength and durability are required.

Material Characteristics and Standards

#4 Trap Rock is a dark-colored, hard, and durable stone with a specific gravity of about 2.8 to 3.0. It has low water absorption (typically below 2%) and a Los Angeles Abrasion value usually less than 30%, indicating resistance to wear. The material is clean, free from clay, silt, and organic impurities, and meets ASTM C33 or ASTM D448 gradation requirements for coarse aggregate. It is also compliant with Department of Transportation (DOT) standards for use as a base and subbase material.

• Particle size: 1 to 3 inches (approx. 25 to 75 mm)
• Material type: Basalt or diabase (trap rock)
• Shape: Angular, crushed
• Absorption: <2%
• Compressive strength: High

Common Applications

#4 Trap Rock is primarily used as a base material in construction projects that require strong support and resistance to shifting. It is not suitable for direct pedestrian or vehicle traffic due to its large size and rough surface. Typical uses include:

• Base and subbase layers for highways and heavy-duty pavements
• Railroad ballast
• Drainage and erosion control systems
• Concrete and asphalt aggregate (structural uses)
• Riprap for slope and shoreline stabilization

Limitations and Misuse

#4 Trap Rock is too coarse for use as a finished surface on walkways, driveways, or patios. Walking or driving directly on this material is not recommended. Its large, angular pieces can be difficult to spread evenly without machinery, and the size makes it unsuitable for landscaping finishes where a finer appearance is desired. This product is not a substitute for common base gravels used in light-duty residential applications.

Technical Specification Table

Typical Installation and Handling

#4 Trap Rock is installed in thick layers, often 6 to 12 inches deep, depending on load requirements. The material is placed and compacted in lifts to ensure interlock and minimize future settling. Due to its size, it is not suited for spreading by hand and usually requires mechanical equipment for placement and compaction. Larger pieces may require additional leveling or screening where a smoother surface is needed for subsequent layers.

Price Examples for #4 Trap Rock Delivery

Gravelshop provides #4 Trap Rock across the United States. Prices vary by region, delivery distance, and local supply. The table below shows sample prices for selected locations. Each price includes both the cost per ton and the delivery charge. All prices reflect standard delivery terms and are subject to local availability and conditions.

These price examples demonstrate the range of costs for #4 Trap Rock delivered to different locations. Delivery charges depend on distance and local logistics. Enter your ZIP code on Gravelshop.com to see pricing for your area.

Ordering and Delivery Process

Ordering #4 Trap Rock from Gravelshop is straightforward. You can view prices and delivery options by entering your ZIP code on the website. All prices include delivery. After placing your order, you will receive a confirmation email with payment and shipping details. Delivery is made by independent trucking companies, and the driver will select the best unloading spot based on site access. Material is delivered in bulk and left at the agreed location, even if you are not present.

Summary Table: Key Facts About #4 Trap Rock

Ordering Information and Site Access

Gravelshop delivers #4 Trap Rock in bulk quantities throughout the United States. Minimum order sizes may apply, depending on your location. Road access to the delivery site must be at least 12 feet wide and suitable for heavy trucks. If site access is limited, material will be unloaded as close as possible. Gravelshop does not spread or install the material; only delivery is provided. All orders are subject to US law and local regulations. Prices include sales tax, environmental charges, and delivery.

Key Takeaways

• #4 Trap Rock is intended for use as a heavy-duty base, not as a finished surface
• Material interlocks for stability under heavy loads
• Order and delivery are managed online with clear, all-inclusive pricing
• Material is delivered in bulk and left at the designated location

For more information, including a material calculator and detailed delivery terms, visit Gravelshop.com or contact our customer support team. All orders are confirmed by email, and you may select your preferred delivery date and time during checkout.