For every building and renovation project, you’ll need the right tools and tool accessories. In projects involving attaching objects to concrete foundations, or walls made of brick, block or stone, the use of drills and drill bits makes the connecting elements—masonry anchors – possible. The tools and bits drill holes to the required depth, so items like handrails, wall brackets or bulky machines are securely anchored and won’t budge. This guide delves into the different types of masonry drill bits, the differences in design, and the materials in which they work best. 
What Are Masonry Drill Bits?
Drill bits come in varying shapes, sizes and design specifics to efficiently and quickly make holes in the base material. Most tradies are familiar with regular twist drills, available in varying points, flutes and shanks, and can cut, drill and bore in most common materials. However, these bits will struggle against tougher materials like concrete, concrete blocks, solid and hollow bricks, and stone. They’re easy to blunt, heat up quickly, and don’t have enough strength to pierce through without damaging the bit, the workpiece or the drill.
This is where masonry bits come in. They’re a more robust take on regular bits, created to make drilling, cutting and boring into masonry a breeze. To choose what’s right for your project, consider masonry bit designs, material composition, tool compatibility and available sizes.
Masonry Drill Bit Designs
Tips
Masonry drill bits are recognisable by their distinct arrowhead tip designs. The tips are wider than the bit body to prevent jamming. They come in two types – tips that are welded onto the bit body and inserted tips.
Welded tips are suited to hard materials and faster stock removal, whereas inserted tips remain sharper for longer, but might struggle in harder masonry. The number of cutting edges can also vary. Chisel-like twin cutting edges with centring points produce clean, straight holes and optimal guidance while drilling.
Crossed tips with four cutting edges are better at fast stock removal, but also protect the bits when coming into contact with rebar. Both types can include wear markers to ensure that they can still be used without the risk of snapping.
Flutes
Flutes are the spiral grooves, or channels, along the length of the drill bit. They differ from the flutes in twist drills in that they are designed to remove dust and debris, while tips and cutting heads are used for drilling and cutting.
Masonry bits can be single or double-fluted. Bits with two flutes work better for higher stock removal, meaning faster drilling. In addition, shorter flutes with fewer rotations get more dust out in thicker masonry. Different designs also perform differently in different masonry. For hardened and thicker concrete, symmetrically shaped flutes do a better job, while brittle masonry, such as brick and hollow block benefits from straight flutes.
Choosing the Right Shank
Shanks are some of the key design aspects in masonry drill bits. They determine with which tools the bits are used, and hence the types of masonry you can drill. For light-duty applications in softer and thinner workpieces, standard or straight shank bits fitting to standard jaw chucks in portable drills will meet most needs. These can be used in brick, harder ceramics and most types of concrete when optioned in drills with a hammering action.
Straight shank bits in regular drills don’t have the grunt to work in solid concrete, but the sharpened tips can drill through brick, tiles, and hollow concrete blocks. The same bits can be used for house repairs and jobs when drilling into wood, plastics and softer metals. Just don’t expect the same level of precision and finish as bits specifically intended for those materials,
If you rely on impact drivers to get work done, then there are masonry bits with hexagonal shanks> these work in wood, plastics, hollow and solid bricks, and tiles. But like straight shank bits they’ll struggle in concrete, and are relegated for specialist uses, such as edge work where there’s the risk of chipping.
For professional uses, look to SDS Max and SDS Plus Masonry Drills. These fit chunks of SDS rotary hammer drills. The tools have enough torque for heavy-duty drilling tasks, pushing and pulling bits in a hammering action to quickly chip away even through the hardest materials. This includes hardened and reinforced concrete, and all masonry regardless of thickness. SDS Max bits are suited to thicker materials, with bits in 18mm shank diameters, while SDS Plus bits average 10mm and are suited to lighter construction and engineering tasks.
The bits are recognisable by their slotted cylindrical shanks, that lock into the drills. Ensure that you purchase the SDS drill bit for the matching SDS drill. They are not interchangeable. SDS Max bits are longer and wider (some reaching 2500mm), while SDS max bits average 500mm, with shorter and longer bits available.
Materials
Materials in masonry and concrete drill bits differ. High-speed steel is common in general-purpose bits that suit DIY or jobs around the house. These usually are with straight shanks and are used in regular drills. Cobalt bits are one rung up in overall strength, but these still won’t work in tougher masonry.
For better piercing and drilling, SDS bit tips have tungsten carbide, titanium nitride or diamond inserts. These not only last longer but retain a uniform shape (for precise holes) and lower the risk of bits chipping or snapping. And since concrete is porous and corrosive, most bits are coated with black oxide to ensure rust doesn’t cause damage or impede workflow.
Sizing Bits According to Tasks
Sizes in masonry drill bits refer to tip diameters, flute lengths and overall lengths. Generally, straight bits are shorter and narrower, with overall tip diameters reaching 12mm, flute lengths of up to 250mm and overall lengths of up to 310mm. SDS Max variants grow in all directions. They come in working lengths (how far the flute penetrates) of up to 2360mm, and overall lengths of 2500mm. Their SDS plus siblings round out to 1000m in the biggest bits, but smaller sizes (200-500mm) are more common.
The important thing to remember is to get a masonry bit with tips that suit fasteners and anchor diameters to ensure a snug fit and bits that can achieve the right drilling depth.