How to break up concrete with an SDS drill

What an SDS drill can and cannot break

A typical SDS plus drill with around 2 to 3 joules per blow handles floor and wall tiles, render, small areas of thin concrete, mortar beds and chasing for cables. It will chip at a thick slab, but slowly. SDS max drills and breakers deliver far more energy per blow and suit thick concrete and large areas.

Your drill must have a hammer only or chisel mode. Combi drills cannot chisel; their hammer works only while the chuck turns. See SDS drill vs combi drill.

Choosing chisels

A point chisel concentrates the blow to crack concrete. A flat chisel splits along a line and removes material. A wide tile chisel gets under tiles and adhesive. A channel or gouge chisel makes neat cable chases. Make sure chisels match your chuck: SDS plus and SDS max are not interchangeable.

Grease the shank lightly as you would a bit; see how to use an SDS drill.

Technique step by step

Work methodically from an edge, not the middle. Concrete breaks far more easily when it has somewhere to move, so an open edge or a line of drilled holes saves a lot of time and effort.

1. 1

   Clear the area, check for pipes and cables below and wear all protective gear.

2. 2

   Fit the chisel, set hammer only mode and, if your drill has it, lock the chisel at the angle you want.

3. 3

   Start at an edge or crack. Hold the drill at a low angle and take small bites.

4. 4

   For thicker concrete, drill a line of holes first with a large masonry bit, then chisel between them.

5. 5

   Lever pieces up with a bar rather than forcing the chisel deeper.

6. 6

   Rest regularly. Vibration exposure builds up quickly with chiselling.

See SDS drills with chisel mode →

Removing tiles

Start at a broken tile or grout line. Use a wide tile chisel at a shallow angle so it slides under the tile and adhesive. On walls, work from the top down and support the plasterboard if you want to keep it. On floors, wear knee pads and keep the chisel flat to avoid gouging the screed.

For a few tiles near a fitting, a multi-tool with a grout blade can be gentler; see how to remove grout with a multi-tool.

Safety, dust and vibration

Chiselling throws sharp fragments, so wear safety glasses or goggles, gloves and boots. Concrete dust contains silica; dampen the surface where possible and wear a suitable FFP3 mask. Hearing protection is essential.

Vibration exposure from chiselling can reach HSE action levels quickly. Take regular breaks and read power tool vibration explained.

Note:Never break concrete over unknown services. Check plans, use a cable detector and, for any gas or electrical service, ask a qualified professional. Wear suitable protection throughout.

When to hire a breaker

If the job involves a slab thicker than a typical garden path, a large patio or foundations, hire a proper breaker. It will finish in hours what an SDS plus drill might take days to do, with less wear on your drill. See hire or buy an SDS drill for how to decide.

For a small job, a cordless or corded SDS plus drill with chisel mode is usually enough. Plan how you will remove the rubble too. Broken concrete is heavy, so use strong rubble bags you can still lift, and check your local council rules for disposing of hardcore.

Frequently asked questions

Can a combi drill chisel? No. A combi drill has no hammer only mode and its hammer action is far too light for chiselling.

Which SDS chisel is best for tiles? A wide tile chisel or flat chisel held at a low angle.

Can a cordless SDS drill break concrete? Yes for small areas, but it uses batteries quickly. Bring spare packs.

How do I control dust when chiselling? Dampen the surface, ventilate the room and wear an FFP3 mask.