Drilling brick without splitting it

Drilling brick requires method to avoid cracks and chips. This guide is aimed at DIYers who have to fix shelves, lights or radiators to a brick wall. You will learn to choose the drill, the bit and the anchors, then to drill without forcing.

Choosing the drill, the bit and the anchors

A 600 W hammer drill is enough for brick, unlike concrete which requires a rotary hammer. Use a masonry bit with a carbide tip at the diameter of the anchor, generally 6 mm for a 6 x 30 mm anchor. Wood or high-speed steel bits are destroyed at once.

1. Identify the type of brick: solid, hollow or aerated
2. Choose the bit diameter according to the anchor, 6 or 8 mm
3. Check the condition and length of the carbide bit
4. Set the drill to hammer mode for brick
5. Plan safety glasses and a dust mask

Marking and drilling without excessive hammer action

Mark the point with a pencil, then centre-punch the brick with a punch or a nail to guide the bit. Start the hole at slow speed without hammer action, then drill in short bursts removing the bit to evacuate the dust. In hollow brick, switch off the hammer action as soon as you enter the void.

Adapting the anchors to hollow brick

For solid brick, standard expansion anchors are enough. For hollow brick, use winged or knot-expansion anchors that open out behind the wall. The anchor must go in without forcing and the screw reach the bottom for an optimal grip.

Precautions and mistakes to avoid

• Forcing by pressing hard on the drill, which splits the brick
• Using a blunt bit that heats up and cracks the material
• Drilling less than 5 cm from a brick edge or corner
• Hammering the anchor into a too-small hole

With a suitable bit and a gentle progression, the brick drills cleanly without cracking. Your fixings will be solid and the wall will remain impeccable. Do not hesitate to practise on a brick offcut if in doubt.