How to Drill Through Asphalt | Asphalt Core Drilling Guide
How to Drill Through Asphalt
Drilling through asphalt is a common task in utility work, roadway construction, and infrastructure projects. Contractors often drill asphalt to install utility conduit, anchor bolts, traffic control equipment, or to take asphalt core samples for testing and inspection.
Using the proper drilling equipment and asphalt core bits helps ensure clean holes, faster drilling, and longer tool life. This guide explains the basic asphalt drilling process and highlights professional equipment used by contractors in the field.
New to core drilling? Learn the full process in our How to Core Drill Concrete guide , which explains drilling setup, equipment options, and safety tips used by professional contractors.
What Is Asphalt Core Drilling?
Asphalt core drilling uses a hollow diamond core bit to cut through asphalt pavement and remove a cylindrical sample or create a clean hole through the surface.
This method is commonly used for installing utility infrastructure, mounting equipment, and performing pavement testing. Compared to breaking or cutting methods, core drilling produces a cleaner hole and minimizes damage to the surrounding pavement.
Common Reasons Contractors Drill Asphalt
- Installing electrical conduit
- Running fiber optic lines
- Water and sewer line access
- Traffic signal installations
- Roadway and pavement testing
- Installing bollards or anchors
Professional diamond core bits are designed to cut cleanly through asphalt and other pavement materials while maintaining durability during repeated drilling.
Step-by-Step: How to Drill Through Asphalt
1. Mark the Drilling Location
Identify the exact location where the hole is required and ensure there are no utilities or obstructions below the drilling area. Accurate positioning helps avoid unnecessary damage to the pavement surface.
2. Select the Correct Core Drill and Bit
The correct machine depends on the diameter of the hole and the jobsite conditions. Portable handheld drills are often used for smaller holes, while larger drilling projects may require gas powered rolling core drills for improved stability and power.
3. Attach the Diamond Core Bit
Secure the asphalt core bit to the drill spindle and ensure the connection is tight before beginning the cut. Using a high quality bit designed for asphalt helps improve drilling speed and overall performance.
4. Begin Drilling Slowly
Start drilling at a controlled speed to allow the bit to establish a clean cutting path through the asphalt surface. Maintaining steady pressure helps produce a smooth and accurate hole.
5. Remove the Asphalt Core
Once the drilling depth is reached, stop the drill and remove the cylindrical asphalt core. Clear any remaining debris before installing the required utility line or anchor.
Choosing the Right Equipment
Contractors use different types of drilling equipment depending on the job requirements. Portable handheld drills are ideal for mobility and smaller diameter holes, while larger machines provide greater power and stability for heavy-duty drilling.
Popular equipment used for asphalt drilling includes:
Concrete vs Asphalt Drilling
While the drilling process is similar, asphalt is generally softer than concrete and requires less cutting force. However, asphalt can still generate heat and wear on the diamond segments if the correct bit is not used.
Concrete drilling may require slower speeds and water cooling when cutting reinforced material, while asphalt drilling often allows faster drilling depending on the surface composition.
Selecting the correct bit and machine helps improve drilling efficiency and extend equipment life.
Frequently Asked Questions
Can you drill through asphalt with a core drill?
Yes. Diamond core drills are commonly used to drill clean holes through asphalt pavement for utilities, anchors, and roadway installations.
Do you need water when drilling asphalt?
Water is sometimes used to help cool the bit and remove debris, although asphalt drilling may also be performed dry depending on the equipment.
What size core bit should be used for asphalt?
The correct bit size depends on the required hole diameter and the utility or anchor being installed. Contractors typically choose a bit slightly larger than the object passing through the pavement.
