Hammer Drill vs. Impact Driver: What’s the Difference?
As a DIYer, have you wondered about whether to use or rent a hammer drill vs an impact driver? Here we explain how to easily make that decision.
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Hammer drills and impact drivers are some of the most frequently confused tools for new DIYers. The confusion is understandable. After all, both are loud, feature a striking mechanism and drive fasteners.
The truth is, these tools are actually different. While they may sound and look similar and even share some functions, they have their own specific strengths and weaknesses.
What Is a Hammer Drill?
A hammer drill is a power drill used to bore holes through tough surfaces. Hammer drills look and act like traditional power drills, with standard chucks, triggers and speed controls, but they’re larger and more powerful. Plus, like a standard power drill, a hammer drill spins clockwise and counterclockwise.
It features an additional “hammer” setting that activates a mechanism inside the drill. The “hammer” strikes the back of the chuck. These strikes, AKA “blows,” send an impact down the length of the drill bit and into the material being drilled. This action punches the bit forward with every blow. Some hammer drills can create as many as 48,000 blows per minute (BPM)!
Generally speaking, hammer drills cost between $100 and $250 for battery-operated models. Corded models cost between $75 and $200. With modern advancements in lithium-ion technology, battery-operated models are popular for their portability, although some corded models offer more power.
What Is an Impact Driver?
An impact driver is a power tool used to drive fasteners, like screws and lag bolts.
These tools feature quick-change ball-bearing chucks, rather than chucks with jaws found on typical drills. These special chucks can’t utilize standard drill bits with round shanks, but they’re compatible with hex-shank, quick-change, impact-ready driver or drill bits. Impact drivers are also typically shorter and stubbier than standard drills.
Impact drivers can spin fasteners clockwise or counterclockwise, like a standard drill, and at high speeds. However, once the impact driver feels a certain amount of resistance on the fastener, it automatically activates a rotational impact anvil. Anvil strikes are known as “impacts,” and some drivers offer up to 4,000 impacts per minute (IPM)!
Each impact drives the bit’s rotation with additional torque, allowing the tool to drive longer and bigger fasteners than it could without the anvil.
Also, an impact driver’s speed can be deceiving. These tools don’t rotate in a steady, constant direction. They actually drive the bit forward a little before quickly twisting the bit backward. It’s helpful to think of it as two steps forward, one step back. This helps prevent the tip of the driver bit from slipping, resulting in fewer stripped fasteners. This happens so quickly, it’s unnoticeable.
Cordless impact drivers generally cost between $100 and $200. Corded models are rare.
Hammer Drill vs. Impact Driver: What Are They Used For?
Both hammer drills and impact drivers can serve multiple purposes, but they do shine inspecific uses.
Hammer drill uses
If you’ve tried to drill a hole in brick, tile or concrete, you know how difficult the job can be. These are situations where a hammer drill can be indispensable. With the hammer function activated, the drill punches the tip of the bit forward into the material, making short work of an otherwise monotonous task.
Some common uses for hammer drills include:
- Starting and drilling a hole on a slippery tile or glass backsplash.
- Drilling through basement concrete to attach framing lumber.
- Drilling into concrete steps for attaching handrails.
- Hanging TV wall mounts, shelves or pictures on brick walls.
- Drilling holes in a garage floor for permanently fixing power tool stands to the ground.
- Drilling holes for attaching mechanical system brackets to a concrete utility room floor.
Note: Drilling through masonry surfaces with a hammer drill requires special masonry bits.
Impact driver uses
Impact drivers are all about packing as much punch as possible into a small tool. They’re helpful for driving smaller fasteners at high speeds, as well as driving longer fasteners without breaking out wrenches or sockets.
Common uses for impact drivers include:
- Driving smaller screws into dense or thick wood. (They would split thin wood.)
- Driving longer, heavy-duty screws quickly, like when hanging cabinets or other heavy objects.
- Fastening a deck ledger board with lag bolts.
- Driving screws in tight spots, like between joists or studs, or inside cabinets.
Hammer Drill vs. Impact Driver: Key Differences
These are key differences between hammer drills and impact drivers:
- Impact drivers must use hex-shank impact-ready bits, while hammer drills accept all bits.
- Impact drivers are typically much smaller, shorter and lighter than hammer drills, making them more useful in tight places or awkward spaces.
- Hammer drills often have speed and torque settings, whereas impact drivers have pressure-sensitive triggers to control speed.
- Users can select when to use the hammer setting on a hammer drill, but impact drivers engage their impact anvil automatically.
- Impact drivers maintain better contact with fastener than a hammer drill, even with the hammer setting disengaged.