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Drilling into brick mortar is usually easier and safer than drilling into the brick itself—but only if you use the right bit, speed, and anchor. Mortar is softer and more forgiving, yet old or weak joints can crumble quickly when overheated, struck too aggressively, or drilled too close to an edge.
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Choose the right location
Drill near the center of the mortar joint, not right against the brick. A horizontal joint gives you the most room for error, while a vertical joint is useful for lightweight fixtures but may be narrower and more weathered. Stay at least 1/2 inch from the edge of a brick and avoid visibly cracked, loose, or deeply eroded mortar.
Check what is behind the wall before drilling. Exterior brick veneer may have a cavity, sheathing, or framing behind it. Interior brick can conceal electrical cable, plumbing, or old fasteners. Do not assume a mortar joint is safe simply because it is soft.
Pick the drill and bit
For small holes in sound mortar, a regular cordless drill and a sharp masonry bit are usually enough. Use a hammer drill when the joint is hard, the hole is larger than about 1/4 inch, or you need to drill several holes. Hammer action saves time in solid masonry, but it can pulverize weak mortar.
An impact driver is not the first choice for drilling masonry. Its rotational impacts can grab and chatter, enlarging the hole and damaging the joint. It can work with a suitable hex-shank masonry bit for occasional small holes, but a drill gives you better control.
| Job | Best tool | Why |
|---|---|---|
| One or two holes up to 1/4 inch | Regular cordless drill | Most control and least risk of breaking soft mortar |
| Several holes in hard mortar | Hammer drill | Faster cutting with less pressure |
| Very soft, crumbly, or historic mortar | Regular drill, low speed | Hammer action can turn the joint into powder |
| Driving screws into a predrilled anchor | Drill or impact driver on low power | Use the impact driver only after the hole and anchor are properly set |
Use a carbide-tipped masonry bit, not a standard twist bit. Match the bit diameter to the anchor manufacturer’s specification. A carbide-tipped masonry bit set is more useful than a single oversized bit because common anchors may require holes from 3/16 to 3/8 inch.
Set up before drilling
Mark the hole with a pencil, then place a small piece of painter’s tape over the mark. The tape helps keep the bit from skating across dusty mortar. It also gives you a visible depth reference if you mark the required hole depth on the bit with tape.
Wear eye protection. Drilling overhead or into old mortar calls for a dust mask as well. Keep a vacuum nozzle near the hole while drilling, or stop periodically to clear dust. Packed dust can make the anchor seem tight before it has reached solid material.
Set the drill to low or medium speed. Masonry bits cut by abrasion, so pressing harder and spinning faster does not necessarily help. It mainly creates heat and dust. Start without hammer mode, especially on an unfamiliar joint. If the bit barely advances after 10 to 15 seconds of firm, controlled pressure, switch to hammer mode briefly and reassess.
Drill the hole without destroying the joint
Hold the drill square to the wall. Start slowly until the bit creates a shallow ring, then increase speed slightly while keeping steady pressure. Do not rock the drill to widen the hole. If the hole needs to be larger, use the correct larger bit rather than twisting the smaller one sideways.
Drill only as deep as required. For a plastic expansion anchor, the hole is commonly about 1/4 inch deeper than the anchor so dust and displaced material have somewhere to go. Follow the anchor instructions instead of guessing. Pull the bit out once or twice during drilling to clear dust, particularly in holes deeper than 1 inch.
Stop immediately if the joint begins flaking beyond the hole, the bit suddenly drops into a void, or the brick around the joint starts cracking. A larger hole is not a stronger hole. Move several inches away, choose a lighter-duty anchor, or repair the joint before fastening.
Choose an anchor that suits mortar
Light-duty plastic expansion anchors work well for small signs, cable clips, and other low-load items. They are inexpensive and are often the best choice when the mortar is sound. For heavier shelves or hardware, use a masonry screw only when the hole can be drilled accurately and the remaining mortar is firm.
For loads that pull outward, such as a bracket or handrail, mortar is a poor substitute for brick or structural framing. Consider locating a stud, fastening through the brick veneer into framing, or using an engineered chemical or sleeve anchoring system. A masonry screw anchor kit is convenient for moderate-duty work, but its holding strength depends heavily on hole depth and the quality of the joint.
Do not overtighten. Expansion anchors can split weak mortar, while masonry screws can strip the hole if driven too fast. Tighten until the fixture is secure, then stop. For controlled installation, use a regular drill with a clutch rather than full power on an impact driver.
When to repair or avoid the joint
If the mortar turns to sand with light finger pressure, drilling is only a temporary solution. Repointing may be necessary before installing anything that could injure someone if it falls. Historic brickwork may also use soft lime mortar that should not be aggressively drilled or replaced with hard modern cement without professional advice.
For ordinary household tasks, a sharp masonry bit, low speed, careful depth control, and a modest anchor are enough. If you regularly drill brick, a cordless hammer drill is worth buying. If you only need two small holes in sound mortar, the cheaper regular drill is the better tool because it gives you more control and avoids unnecessary damage.