You need a hammer drill or a rotary hammer to drill into concrete. A standard drill won’t cut it because concrete is too hard for simple rotation alone. These tools combine spinning with a rapid hammering action that pulverizes the material as the bit turns, and the right choice depends on the size of the hole and how much concrete work you’re doing.
Hammer Drill vs. Rotary Hammer
These two tools look similar but work very differently on the inside. A hammer drill uses two ridged metal discs that vibrate against each other as they spin, driving the bit forward with a rapid chattering motion. It works well for lighter jobs: anchoring screws, mounting brackets, drilling holes up to about half an inch in diameter. Most hammer drills also function as regular drills, so you get a versatile two-in-one tool.
A rotary hammer uses a piston mechanism that generates significantly more force per blow. Instead of vibrating, it delivers distinct, powerful strikes that chew through concrete much faster and with less effort from you. If you’re drilling holes larger than half an inch, going deeper than a few inches, or drilling more than a handful of holes in a session, a rotary hammer is the right tool. The difference in effort is dramatic. What takes minutes of steady pressure with a hammer drill can take seconds with a rotary hammer.
For most homeowners hanging shelves, installing a TV mount, or setting a few concrete anchors, a hammer drill is enough. For anyone doing regular concrete work, installing larger anchors, or drilling into thick slabs and foundations, a rotary hammer pays for itself in time and comfort.
SDS Plus vs. SDS Max Chucks
Rotary hammers use a special chuck system called SDS, which lets you swap bits with one hand by simply pushing them in or pulling them out. There are two main sizes, and they’re not interchangeable.
SDS Plus is the more common system. It uses a 10mm shank and accepts bits from 5/32 inch up to 1 inch in diameter. This covers the vast majority of residential and light commercial work: concrete screws, sleeve anchors, drop-in anchors, and small-to-medium holes for plumbing or electrical. SDS Plus rotary hammers are lighter, more affordable, and easier to handle overhead or in tight spaces.
SDS Max uses an 18mm shank and handles bits from 3/8 inch to over 2 inches in diameter. These are heavy-duty machines built for large-diameter holes, deep drilling into thick concrete, and demolition work like breaking up slabs with a chisel attachment. You cannot fit an SDS Max bit into an SDS Plus tool. If your work regularly calls for holes over 1 inch, SDS Max is the system you need.
Choosing the Right Drill Bit
The bit matters as much as the drill. Standard masonry bits have a carbide tip brazed onto the end, forming two cutting edges. These 2-cutter bits work fine for smaller holes under half an inch. For holes at half an inch and larger, a 4-cutter bit with an X-shaped carbide tip drills faster, runs cooler, and lasts longer. The cross design distributes cutting force more evenly across the hole. Two-cutter bits exist in larger sizes, but they’re slower and wear out sooner, so they’re only worth considering if upfront cost is your main concern.
For very large holes (think running a 3-inch pipe through a foundation wall), you’ll need a diamond core bit. These are hollow cylinders with diamond segments on the cutting edge that grind through concrete and can handle embedded rebar. Core bits require a dedicated core drill rig or a rotary hammer with enough power to turn them at the correct speed.
What to Do When You Hit Rebar
Reinforced concrete often has steel rebar inside, and a standard masonry bit will stop cold when it hits metal. You have a few options. The best approach is to use a rebar scanning tool before you drill to find the steel and adjust your hole location. If that’s not possible, specialty rebar cutter bits can shave through the steel, but there’s a critical rule: switch your hammer drill or rotary hammer out of hammer mode. These bits are designed to cut like a twist drill. The hammering action will shatter the carbide tip on the first hole.
When cutting through rebar, use low speed with steady, even pressure. Applying cutting oil reduces heat buildup that can temper and harden the steel. Once you’re through the rebar, stop the rebar cutter bit before it hits concrete on the other side, since concrete dulls these bits quickly. Then switch back to your masonry bit and hammer mode to finish the hole.
Corded vs. Cordless
Cordless rotary hammers have improved dramatically and now handle most concrete drilling tasks that used to require a cord. In a recent head-to-head test of 1-inch SDS Plus rotary hammers, an 18V Makita drilled 66.5 holes on a single 4Ah battery, the most efficient tool in the group at 0.92 holes per watt-hour. Higher-voltage tools like DeWalt’s 60V FlexVolt delivered more raw power, especially for 1-inch holes and chiseling, but at the cost of extra weight and lower energy efficiency per watt-hour.
For occasional use or jobs where you’re drilling a dozen holes or fewer, an 18V cordless rotary hammer with a good battery is more than capable. If you’re drilling dozens of large holes in a day, such as installing drop-in anchors on a commercial job, corded tools still offer unlimited run time and consistent power. A second battery largely solves the runtime issue for cordless users, though the upfront cost is higher.
Dust Control While Drilling
Drilling concrete produces fine silica dust, which is a serious lung hazard with repeated exposure. OSHA requires that handheld hammer drills and rotary hammers use a dust collection shroud or cowling connected to a vacuum with a filter rated at 99% efficiency or greater. The vacuum also needs a filter-cleaning mechanism to maintain airflow. When you’re done drilling, clean out each hole with a HEPA-filtered vacuum rather than blowing the dust out.
If you follow these controls, no respirator is required regardless of how many hours you drill per shift. Many major tool brands sell bolt-on dust collection attachments designed for their rotary hammers, and compact HEPA vacuums built specifically for this purpose. For a homeowner drilling a few holes once, the risk from a single exposure is low, but a simple N95 mask and working in a ventilated area is still smart practice.
Tips for Clean, Fast Holes
Let the tool do the work. The most common mistake is pushing too hard, which overheats the bit and actually slows you down. Apply steady, moderate pressure and let the hammering action break up the concrete while the rotation clears the debris. If the bit feels like it’s bogging down, back it out slightly to clear dust from the hole, then continue.
Periodically withdrawing the bit also prevents it from binding in deeper holes. For holes over 3 or 4 inches deep, pull the bit out every inch or so to let debris clear. If you’re drilling into especially hard concrete with dense aggregate, you may feel the bit grab or slow intermittently as it hits stones. Maintain even speed and pressure rather than forcing it. Pushing harder just generates heat, which polishes the carbide tip and reduces cutting performance.
Mark your desired depth on the bit with a piece of tape, or use the depth stop rod that comes with most rotary hammers. This prevents over-drilling, which weakens anchors by giving them too much room in the hole.