To figure out what is behind your wall before drilling, combine scanning tools with a manual investigation.
Tie the magnet to a piece of string or floss and run it horizontally along the wall an inch away from the surface. If the magnet is strong enough, it will stick to the wall when it comes across any screws or nails that were hit into the stud during the wall's construction.
Yes, your phone can function as a stud finder, but with a catch: it uses your phone's built-in magnetometer (which powers the compass) to detect the metal screws or nails hidden in your drywall, rather than the wood itself.
To safely drill into a wall, identify the wall material by tapping it—a hollow sound indicates drywall, while a high-pitched, dense sound indicates brick or concrete. Then, use a wall scanner to check for hidden wires or pipes, and avoid drilling directly above or below outlets and switches.
“One common rule is to avoid drilling around light switches and sockets, as the electrical wires can go horizontally and vertically around these fixtures,” Williams explains. “You can also get an idea of where wires and pipes run by looking in the attic and basement to see where they go up or down through framing.”
Investing in professional equipment, such as a cable avoidance tool, is the safest option to avoid wires. However, if you don't have access to this, most wiring runs horizontally 6 inches or 12 inches above the receptacle, so avoid these areas. If it is possible, only drill shallow holes.
Yes, you can drill into drywall. However, because drywall is soft and hollow behind, you cannot hang anything heavy in it without using a wall anchor. For lightweight items, you can often just use a self-drilling anchor and a screwdriver.
The most foolproof way to avoid hitting wires is to trace their likely paths, scan the wall with an active voltage detector, and physically "feel" behind the drywall before finalizing your hole.
Never drill directly above, below, or to either side of outlets, light switches, and hose bibs, as utility lines typically run straight up, down, and horizontally from these fixtures. Additionally, avoid drilling within 6 inches of ceilings, corners, and floorboards where home-run electrical cables and baseboard plumbing frequently travel.
The easiest, most foolproof way to find a wall stud is using a strong rare-earth magnet. Since drywall is attached to studs with metal screws or nails, sliding a magnet over the wall will reveal where these fasteners are buried.
Studs in most homes are spaced 16 or 24 inches apart on center, meaning the distance from the center of one stud to the next. Interior walls are usually 16" OC, while garages, basements, and exterior walls may use 24" OC for energy efficiency.
For consumers and professionals, "see-through-wall" devices use advanced radar or thermal imaging to display studs, pipes, wires, or even movement behind drywall and concrete. Popular, accessible options include the Walabot DIY 2 for smartphone-based 3D scanning and the Bosch D-TECT200C Wall/Floor Scanner for heavy-duty professional detection.
Studs run vertically behind the drywall in your home or apartment. Knocking, using magnets, and flashlights are a few ways to help you locate a stud without a stud finder.
If your wall studs are spaced 24 inches apart, your home was likely built using a technique called "advanced framing" (or optimum value engineering), or it features non-load-bearing interior walls.
To safely drill into a wall, identify the wall material by tapping it—a hollow sound indicates drywall, while a high-pitched, dense sound indicates brick or concrete. Then, use a wall scanner to check for hidden wires or pipes, and avoid drilling directly above or below outlets and switches.
You know you've hit a wire if your circuit breaker trips, you see a flash of light, or you hear a sudden "pop" or "bang". Additionally, you might notice sparks from the hole, the smell of burnt plastic, or your drill bit might show signs of arcing (burn/melt marks).
Wall Scanners. Wall scanners are used prior to starting drilling work on walls of different types. The easy-to-use units are designed to detect wood and metal studs, as well as live electrical wires. For professionals and home users alike.
Common In-Wall Hazards (Wires, Pipes, and More)
The most common of these is electrical wiring since most of it is hidden within the walls to keep them safe and out of sight. Another common hazard is plumbing, which is also commonly hidden inside drywalling.
Two common mistakes made during drywalling are improper joint compound application (such as applying it too thickly or not feathering the edges), and failing to stagger the seams across different studs, which weakens the wall and increases the risk of cracking.
Self-drilling screws, which often feature the TEK and ZIP brand names, have drill-bit points that assist the drill in biting into metal and other materials so you don't need any pre-drilled holes.
If it calibrates over the stud, it will be ignoring anything of that density, so it will ignore the stud. Letting other objects get near the stud finder once it's been calibrated. Even a pencil, or finger will throw it off so keep your digits well away until you stop moving it and need to mark the wall.