Masonry Drill Bits: How to Drill Concrete and Brick

To drill concrete and brick, use a carbide-tipped masonry drill bit in a hammer drill. For holes larger than about 1/2 in, or many holes in poured concrete, use an SDS-plus bit in a rotary hammer. The bit’s diameter must match the anchor you’re installing: a 1/4 in wedge anchor goes in a 1/4 in hole; a 3/16 in concrete screw needs a 5/32 in hole.

A masonry bit doesn’t slice material like a metal drill bit. Its flat carbide tip chips and crushes the stone, the hammer action breaks it up, and the spiral flutes carry the dust out.

Types of masonry drill bits

Bit type	Shank	Use in	Best for
Carbide-tipped masonry bit	Round or hex	Hammer drill, or a regular drill for soft brick	Brick, block, mortar, occasional concrete holes up to about 1/2 in
SDS-plus bit	SDS-plus (slotted 10 mm shank)	Rotary hammer (SDS-plus)	Poured concrete, anchors, holes from about 5/32 in to 1-1/8 in
SDS-max bit	SDS-max (larger 18 mm shank)	Heavy rotary hammer	Large holes and core bits, roughly 1/2 in and up
Multi-material bit	Round or hex	Drill or hammer drill	Mixed jobs: tile, brick, wood and plasterboard with one bit
Diamond core bit	Various	Core drill or rotary hammer (rotation only)	Clean large holes, through rebar, for pipes and cables

SDS bits only fit SDS tools. The slotted shank lets the bit slide back and forth in the chuck, so the hammer energy goes into the bit instead of the chuck. That’s why a rotary hammer drills concrete several times faster than a hammer drill. If you’re deciding which tool you need, read can a hammer drill be used as a regular drill.

Which bit size for wall anchors?

Use the size printed on the anchor packet. The common ones:

Fastener	Drill bit size
3/16 in concrete screw (Tapcon-type)	5/32 in
1/4 in concrete screw	3/16 in
1/4 in wedge anchor	1/4 in
3/8 in wedge anchor	3/8 in
1/2 in wedge anchor	1/2 in
Plastic wall plug, 6 mm (brown/red)	6 mm, or as marked
Sleeve anchor	Same as the anchor’s diameter

Drill the hole about 1/4 to 1/2 in deeper than the anchor so dust left in the hole doesn’t stop it seating. Then blow or vacuum the dust out: dust left in the hole is the most common reason anchors pull out.

How to drill into concrete step by step

1. Mark and check. Mark the spot, and scan for pipes and cables first in walls and floors.
2. Select hammer mode on the hammer drill, or rotary-hammer mode (not chisel) on an SDS tool.
3. Start slowly without hammer for the first few millimetres so the tip doesn’t wander, then switch hammer on and go to full speed.
4. Let the tool work. Push firmly but don’t lean your whole weight on it; too much force slows the hammer action.
5. Pull the bit out every 1 in or so to clear dust, especially in deep holes.
6. If the bit stops dead, you’ve probably hit rebar. Don’t force it: move the hole, or switch to a rebar-cutting or diamond core bit.

Use a depth stop or a piece of tape on the bit to get the depth right, and wear eye protection and a dust mask; concrete dust contains silica.

Drilling into brick and block

Brick and concrete block are softer than poured concrete, so a carbide-tipped masonry bit in a hammer drill is plenty. A few things differ:

• Hollow block and old brick can crack. Start without hammer, and use hammer only if the bit stops progressing.
• Brick or mortar joint? Brick gives the stronger hold for heavy loads like TV mounts. Mortar is softer and easier to patch later, so it suits light items.
• Hollow blocks need hollow-wall anchors, not solid-concrete anchors, if you drill through into the void.

Masonry bit vs other bits

Don’t use a masonry bit for steel: it rubs instead of cutting. For metal, use drill bits for metal such as cobalt or HSS. For glazed tile on a wall, a masonry bit chips the glaze; use a tile or diamond bit until you’re through the tile, then switch to masonry for the brick or concrete behind it. The drill bit size chart converts the fractional and metric sizes used on anchor packets.