Impact Drill vs Rotary Hammer: Which One Drills Concrete?

Short answer: if you are drilling plaster, tile, hollow block or brick, a 680W impact drill is enough. If you are drilling reinforced concrete, you need an SDS-Plus rotary hammer. The two tools look similar and cost about the same, but they break concrete in completely different ways. An impact drill vibrates the chuck as it spins. A rotary hammer fires a piston that strikes the back of the bit, and manufacturers rate that blow in joules. INGCO's RGH9028 rotary hammer is rated at 2.5J and drills up to 26mm in concrete. INGCO publishes no joule rating at all for the ID6808 impact drill, because an impact drill does not deliver a measured hammer blow. That single difference is why one tool sails through a reinforced ceiling slab and the other burns out trying.

In this article

• What is the difference between an impact drill and a rotary hammer?
• Which one do I need for my wall?
• How do the numbers actually compare?
• Do I need more watts or more joules?
• What if there is no power at the site?
• When is a rotary hammer the wrong tool?
• What bits do I need, and can I use my old ones?
• Frequently asked questions

What is the difference between an impact drill and a rotary hammer?

An impact drill (a percussion drill) has two ratchet plates behind the chuck. When you press the tool into the wall, those plates click past each other and shake the bit forward thousands of times a minute. The force comes from you leaning on the tool. Nothing inside the machine is hitting the bit.

A rotary hammer works like a tiny jackhammer. A piston driven by the motor compresses a cushion of air, and that air slams a striker into the end of the bit. The blow is generated by the machine, not by your body weight, and it is measured: INGCO rates the RGH9028 at 2.5J and the RH10506 at 4.5J. The bit also locks in differently. A rotary hammer uses an SDS-Plus shank that slides back and forth inside the chuck, which is what lets the piston reach it at all.

In plain terms: an impact drill scratches its way through masonry. A rotary hammer chisels its way through concrete.

Which one do I need for my wall?

Most modern buildings give you two very different surfaces in the same room, and the honest answer depends on which one you are aiming at.

• Interior partition walls (hollow block, plaster, gypsum, tile): an impact drill is the right tool. It is lighter, cheaper, and it will not blow out the back of a hollow block the way a rotary hammer can.
• Columns, beams, ceiling slabs and any structural concrete: a rotary hammer. This is the poured reinforced concrete that carries the building, and an impact drill will glaze the hole and stall in it.
• Stone facades and old lime walls: a rotary hammer on the low setting, going slowly, because the material is unpredictable.

The practical test: press the bit in for ten seconds. Grey powder and a deepening hole means carry on. Heat, smoke and almost no dust means you have hit concrete or rebar, and the tool is the wrong one.

How do the numbers actually compare?

Every figure below is the manufacturer's own published specification. Where INGCO does not publish a number, the table says so rather than inventing one.

Specifications as published by INGCO on the RGH9028 and RH10506 product pages. Prices are Azar Group prices at the time of writing.

Do I need more watts or more joules?

Joules, almost always. Watts describe how much electricity the motor draws. Joules describe how hard the tool actually hits the wall. Two rotary hammers can sit 250W apart and behave very differently: the 800W RGH9028 delivers 2.5J, while the 1050W RH10506 delivers 4.5J, which is nearly double the blow for a 30 percent bump in wattage.

A useful rule for choosing:

• Up to 2.5J: anchor holes for shelves, TV brackets, water heaters, curtain rails, satellite dishes. This covers most household jobs.
• 4J and above: daily professional use, deeper holes, larger diameters, and light chiselling of plaster and screed.
• Chiselling all day: stop drilling with a rotary hammer and use a demolition breaker instead.

Buying more joules than you need is not free. Higher energy means more weight, more vibration in your wrists, and more damage if the bit wanders into a hollow block.

What if there is no power at the site?

On a site with no reliable mains supply this changes the answer. A corded rotary hammer needs a stable 220V feed, and a long extension lead on a weak generator will cost you power at the tool. If you work in half-finished buildings, on roofs, or during the hours when the supply is off, a 20V cordless rotary hammer removes the problem entirely.

The trade-off is honest: the cordless CRHLI20268 delivers the same 2.5J as the corded RGH9028, but it is sold as a bare tool. You need a 20V battery and charger, and a 2.0Ah pack will not last a full day of concrete work. Two 4.0Ah packs is the realistic setup, and that pushes the total cost above the corded version.

When is a rotary hammer the wrong tool?

Plenty of the time, and it is worth saying clearly before you spend the money.

• You only drill a few holes a year. If your list is picture hooks, curtain rails and the odd shelf in a block wall, the ID6808 at $24.95 does the job and stores in a drawer.
• You are drilling wood or metal. A rotary hammer's SDS-Plus chuck will not hold ordinary round-shank bits without an adapter, and the hammer action ruins wood. Use a drill or a driver.
• You are driving screws. A rotary hammer has no clutch. It will snap the screw or strip the head.
• You are working in thin hollow block. The hammer blow can punch straight through the web of the block and leave you with a hole no plug will grip.
• You are drilling tile. Turn the hammer function off entirely, or the tile cracks. Start with the drill on rotation only until the bit bites through the glaze.

One safety point matters more than the tool choice: before drilling into any wall in an occupied building, know where the wiring and pipes run. The usual routes are the vertical and horizontal channels above and beside sockets and switches.

What bits do I need, and can I use my old ones?

No, and this catches people out. An impact drill takes round-shank masonry bits in a standard three-jaw chuck. A rotary hammer takes SDS-Plus bits, which have grooves cut into the shank so they can slide inside the chuck while the piston hits them. The two are not interchangeable without an adapter.

For a new rotary hammer, a mixed set is the sensible first purchase. The INGCO SDS-Plus Drill Bit and Chisel Set 10pcs AKD2101 at $13.95 covers the common anchor sizes plus a point and a flat chisel, and the 4pc 5 to 10mm set AKD2048 at $4.95 is enough for small anchor holes. Browse the full range in our INGCO collection and power tools collection.

Frequently asked questions

Can an impact drill drill into concrete?

It can start a hole in soft or old concrete, slowly, and it will struggle in modern reinforced concrete. It has no rated hammer blow, so all the force comes from you pushing. Expect a burnt bit, a hot tool and a shallow hole. For anything structural, use an SDS-Plus rotary hammer.

What is SDS-Plus and do I need it?

SDS-Plus is the bit-mounting standard used by almost every rotary hammer under about 5J. The shank has two closed grooves and two open ones, which lock the bit against rotation while letting it slide back and forth so the piston can strike it. If you buy a rotary hammer, you need SDS-Plus bits. SDS-Max is the larger standard used on heavy breakers and is not compatible.

How many joules do I need for a home rotary hammer?

2.5J covers almost every household anchor hole: brackets, heaters, rails and dishes up to about 12mm diameter. Move up to 4.5J if you drill daily, need deeper or wider holes, or want the tool to double as a light chisel.

Is a cordless rotary hammer as strong as a corded one?

At the same joule rating, yes, for as long as the battery lasts. INGCO rates both the corded RGH9028 and the cordless CRHLI20268 at 2.5J. What you lose is runtime, and what you gain is the ability to work when the power is off. Budget for two batteries if concrete work is a regular part of your day.

What happens if I hit rebar?

The tool will suddenly slow and the dust will change colour to a metallic grey. Stop. Do not lean harder, and do not switch to hammer-only. Move the hole 30 to 50mm to the side, or change to a rebar-cutter bit rated for it. Drilling through the steel weakens the element you are drilling into.