Which Drill Bit for Brick? Choose the Right Type
A loose curtain rail, a spinning wall plug or a cracked brick face usually comes down to one decision made before drilling starts: which drill bit for brick is right for the job? Brickwork is tough, abrasive and far less forgiving than timber or plasterboard. The correct bit, paired with the right drill setting and steady technique, makes fitting fixings quicker and gives them the holding power they need.
For most holes in standard house brick, a good-quality carbide-tipped masonry drill bit is the dependable choice. It is designed to break down mineral materials rather than cut them like a standard HSS metal bit or brad-point wood bit. However, the drill bit is only part of the answer. Brick type, hole diameter, fixing depth and the drill you are using all affect the result.
Which drill bit for brickwork?
For ordinary red brick, engineering brick, concrete block and mortar joints, use a tungsten carbide-tipped masonry drill bit. These have a blunt, chisel-shaped cutting tip and flutes that carry dust out of the hole as you drill. They are available with round shanks for standard drill chucks and SDS-plus shanks for rotary hammers.
A standard masonry bit used in a combi drill is the sensible option for common DIY and trade fixing work, such as fitting shelves, cabinets, exterior lights, gate hardware or pipe clips. Choose a bit from a recognised manufacturer with a cleanly finished carbide tip. Cheaper bits can work for a few holes in soft brick, but they lose their edge quickly in dense masonry and can wander at the start of the hole.
For frequent drilling, larger diameters or very hard brick, move to an SDS-plus masonry bit and an SDS rotary hammer. The SDS fitting allows the bit to slide slightly within the chuck while the hammer mechanism does the heavy work. This produces faster progress and puts less strain on the operator and the drill.
Do not use a standard HSS twist drill bit for brick unless there is no alternative and the material is exceptionally soft. It will overheat, blunt rapidly and struggle to clear dust. Wood bits are equally unsuitable. Their pointed tips are made to locate accurately in timber and can chip the brick surface without making useful progress.
When a diamond bit is the better choice
A diamond core bit is not for routine wall plugs, but it is the right tool for larger, clean holes in brick and blockwork. Electricians and plumbers commonly use diamond cores for extractor vents, waste pipes, ducting and larger service penetrations. Dry diamond cores are often used with a suitable drill and dust control, while wet drilling systems are generally reserved for specialist applications.
For a small hole in a particularly hard facing brick, a diamond-tipped tile or multi-material bit can help establish a neat starting point, particularly where the finished appearance matters. Once the surface is pierced, a masonry bit can often complete the hole. This is useful around glazed bricks or brittle finishes, but it is not normally necessary for everyday brickwork.
Match the bit diameter to the fixing
The hole diameter should match the wall plug or anchor manufacturer’s recommendation, not simply the screw diameter. A 6 mm wall plug usually needs a 6 mm masonry bit, while an 8 mm plug requires an 8 mm bit. Drilling an oversized hole is one of the most common reasons for a fixing that will not grip.
As a practical rule, mark the required depth on the bit with tape, allowing for the plug length plus a little extra room for drilling dust at the back of the hole. If the plug is 50 mm long, drilling to around 55-60 mm is normally appropriate. The screw should be long enough to pass through the item being fitted and engage most of the plug, without bottoming out in the hole.
For heavy loads, do not assume that a larger plug alone solves the problem. The quality and condition of the brickwork matter more than raw diameter. A secure fixing for a boiler bracket, wall-mounted storage, radiator, handrail or awning may require specialist anchors, resin fixings or a fixing position that reaches sound masonry rather than weak mortar. Always check the fixing manufacturer’s load guidance and consider the weight in service, not just the weight of the item when empty.
Choose the right drill mode
A combi drill gives you rotary drilling and hammer drilling. Start in rotary-only mode when positioning the bit on a smooth or hard-faced brick. This helps prevent the tip from skating across the surface and damaging the finish. Once the bit has created a shallow guide, select hammer mode and continue with controlled pressure.
For soft common brick or mortar, hammer mode may be unnecessary at first and can make the hole too loose. Rotary action at a moderate speed often provides better control. On dense engineering bricks, concrete blocks or very hard masonry, hammer action is usually essential. If your cordless combi drill is labouring, the bit is not advancing, or you have a run of holes to drill, an SDS rotary hammer is the more productive option.
Avoid using hammer mode when drilling through ceramic tile, as it can crack the surface. Drill through the tile in rotary-only mode with the correct tile or diamond bit, then change to a masonry bit and hammer action only after reaching the brick or block behind it.
Drill speed and pressure matter
Run a masonry bit at a sensible, controlled speed. High speed and excessive force generate heat, wear the carbide tip and can glaze the cutting edge. Let the hammer action and bit design do the work. Apply firm, steady pressure, withdraw the bit every so often to clear debris, and keep the drill square to the wall.
If you hit a hard spot, do not lean harder into the drill. Ease off, clear the hole and resume at a slower pace. Hard inclusions in brickwork are common, particularly in older properties. Pushing too aggressively risks snapping a smaller bit, damaging the chuck or breaking out the brick face.
Brick, mortar or block: where should you drill?
Where possible, drill into the brick itself rather than the mortar joint. Sound brick usually offers more reliable holding strength and is less likely to crumble around a conventional plug. Mortar can be suitable for light-duty fixings, especially where preserving the brick face is important, but its condition varies widely. Old, sandy or weathered mortar may not provide a dependable anchor.
The exception is when the brick is damaged, very soft or hollow. In these cases, drilling into an intact mortar joint may be preferable, or you may need a specialist fixing designed for hollow or lightweight masonry. Hollow bricks and modern blocks can have thin internal webs, so a normal expansion plug may either spin or distort the material. Use a fixing intended for the substrate and avoid overtightening the screw.
Before drilling an exterior wall, consider what may be behind it. Check for electrical cables, water pipes and gas services using an appropriate detector and by assessing likely cable and pipe routes. Avoid drilling directly above or below sockets, switches and plumbing outlets. On cavity walls, be aware that the brick face may only be around 100 mm thick before the cavity begins, so depth control is essential.
A reliable method for clean brick holes
Mark the fixing point accurately and use a small pilot indentation if the surface is slippery. Fit the correct diameter masonry bit, set the drill to rotary-only mode, and begin slowly. Once the bit has located, use hammer mode if the brick requires it and drill straight to the marked depth.
Remove dust from the hole before inserting a plug. A vacuum nozzle, dust extractor or a few careful withdrawals of the bit will help, but for critical fixings the hole should be properly cleaned. Dust left around a plug reduces friction and can stop resin or mechanical anchors achieving their stated performance. Push the plug in so that it sits flush with the wall surface, then drive the screw without overtightening it.
If the plug turns as you tighten the screw, stop rather than forcing it. Remove the fixing, assess the hole and use a suitable repair or larger fixing system if necessary. Simply increasing screw size in a loose plug rarely creates a reliable result.
Know when to replace the bit
Masonry bits are consumables, especially on site work. Replace a bit when drilling becomes noticeably slower, the tip looks rounded or chipped, or holes begin to oversize and wander. A worn bit wastes battery runtime, makes cordless drills work harder and can turn a straightforward fixing job into an unreliable one.
Keep a selection of quality masonry bits in the common 5 mm, 6 mm, 7 mm, 8 mm and 10 mm sizes, alongside larger SDS bits where your work demands them. For professional results, the aim is not simply to get through the brick. It is to produce a clean, correctly sized hole that gives every fixing a solid foundation.
