Concrete coring—drilling clean, cylindrical holes through concrete—is essential for HVAC, plumbing, electrical, and structural work. The total cost depends heavily on hole diameter, depth, concrete thickness, and whether you hit rebar or embedded utilities. Understanding the pricing breakdown helps you budget accurately and avoid expensive surprises on the job site.
What You're Actually Paying For
Concrete coring isn't a one-size-fits-all service. A contractor prices each hole based on several factors, not just a flat rate. The core diameter (typically 1 inch to 12 inches or larger) directly affects labor and equipment wear. Deeper holes require more time, specialized drill positioning, and coolant circulation. If the concrete is reinforced with rebar or contains post-tensioned cables, the job becomes more complex and costly because the contractor must work carefully around these obstacles.
Typical Price Ranges Per Hole
For standard residential or light commercial work, expect to pay:
- Small holes (1–2 inches): $50–$150 per hole
- Medium holes (3–6 inches): $150–$400 per hole
- Large holes (8–12 inches): $400–$800+ per hole
- Extra-large or specialized holes (12+ inches): $800–$2,000+ per hole
These are single-hole estimates with standard conditions: flat surfaces, single-pass depth (under 12 inches), no obstructions. If you need 10 holes instead of one, most contractors offer volume discounts of 10–20%, since they can set up once and move efficiently.
Factors That Drive Costs Up
Concrete strength and age. New concrete (less than 28 days old) is softer and cheaper to core. Aged, hardened concrete or high-strength mixes (3,500+ PSI) slow drilling and increase tool wear, raising labor costs by 20–40%.
Rebar and embedded materials. Hitting steel reinforcement requires the operator to stop, carefully locate the exact position, and sometimes use specialized non-ferrous cores or hand-drilling methods. Expect an additional $100–$300 per hole if rebar is present.
Access and positioning. Tight spaces, overhead drilling, or confined areas demand extra setup time and sometimes smaller equipment. Vertical or inverted holes cost 25–50% more than horizontal drilling on flat surfaces.
Depth beyond single-pass. Most drills can bore 12 inches in one pass. Depths of 24 inches or more require repositioning, multiple passes, or specialized through-hole rigs, doubling labor time.
On-site cleanup and disposal. Some contractors include core removal and cleanup in the bid; others charge separately ($50–$200 total). Confirm whether the contractor hauls away spoil or leaves it for you.
How to Get Accurate Quotes
Contact 3–5 concrete coring specialists and provide these specifics:
- Exact hole diameter and quantity
- Concrete depth and type (standard, reinforced, high-strength)
- Location and orientation (horizontal, vertical, overhead)
- Any known obstructions (rebar, utilities, electrical conduit)
- Timeline and access requirements
Reputable contractors will want photos or site details before quoting; anyone who gives a price sight-unseen may be low-balling. If you're comparing multiple providers, Mercoly makes it simple to find and evaluate trusted concrete cutting and coring specialists in your area in one place.
Labor vs. Equipment Costs
On small jobs (1–3 holes), labor dominates the bill: a technician and basic core drill rig might cost $400–$600 in total. On larger projects (20+ holes), labor per hole drops significantly while equipment setup and transportation become noticeable line items. If you're considering hiring, ask whether the contractor charges a trip fee or minimum job size.
Timeline Expectations
A single hole typically takes 30 minutes to 2 hours, depending on diameter and depth. Batch jobs with similar holes run faster: expect 10–15 minutes per hole once the rig is positioned. Most contractors can complete 20–30 standard holes in a single day. Scheduling delays often stem from permit requirements or discovering unexpected rebar—not the drilling itself.
Frequently Asked Questions
Q: Will the contractor locate utilities before drilling? A: Reputable concrete coring companies use ground-penetrating radar (GPR) or contact local utility locating services before drilling; this may add $150–$400 to the bid but prevents costly and dangerous mistakes. Always verify their safety protocol upfront.
Q: Can I use a rental core drill instead of hiring a contractor? A: Small-diameter equipment (1–3 inches) rents for $40–$80 per day, but coring requires skill, proper water circulation, dust control, and safety setup; unless you're experienced, DIY typically saves money only on a handful of holes and risks poor results or tool damage.
Q: What's the difference between coring and conventional drilling? A: Coring uses a hollow diamond-tipped bit to remove a cylindrical plug, leaving a clean hole; conventional drilling creates friction and heat, damaging concrete edges and embedding utilities, making coring essential for precision work.
Start by gathering detailed site information and contacting multiple providers to compare pricing and service levels—the quote variance is often eye-opening.