Having trouble finding the timber studs in a wall? How to use a stud finder like a pro

Looking to hang new shelves, install kitchen wall cabinets, or mount a TV on a wall? If you are, you are going to need a secure fixing to ensure they stay in place. However, because wall studs are hidden behind walls, they are not always easy to find.

While you can use the best plasterboard fixings on a wall to support whatever you're putting up, but for extra security and peace of mind, especially when hanging heavy objects, inserting fixings into a timber stud is the answer.

Instead of second-guessing where they are by tapping the wall, a stud finder is the sensible and smart choice for accurate readings. Here, the pros reveal how to get the best out of a stud finder.

Mark Irving

With over 20 years of experience in the building sector and years working for Build & Plumb Mark has developed a wealth of knowledge surrounding building and renovating that he enjoys sharing with others.

Types of stud finder

There are two common types of stud finders, electronic and magnetic. Electronic stud finders are typically more expensive than magnetic stud finders. However, they have more features and can generally detect more behind-the-wall features, such as cables and pipes

Mark Irving, building expert at Build & Plumb, shares how electronic stud finders work: “They operate by sensing changes in material density behind a wall’s surface.” He adds, “When placed against a drywall surface, the device will calibrate the baseline density. Then, as it moves, it will detect increases in density. They can also detect live electrical wiring, metal pipes and deep framing members.”

However, they can be fooled by certain elements, as Irving shares, “While particularly useful for going through thicker drywall, they require a full calibration before each scan and can often be confused by plaster walls, tile, and dense insulation.”

Magnetic stud finders are much simpler and use a strong magnet to do the hard work, as Irving shares, “They are ideal for identifying fasteners and require no batteries or calibration. However, they only work when ferrous fasteners are present and will often miss studs if adhesive was heavily used during installation.”

Shop these stud finders to help find studs, cable and pipes

Using an electronic stud finder

Before you start using an electronic stud finder, Paul Kerr, building specialist at Beatsons Building Supplies, offers some sensible advice: “First and foremost, you need to make sure the stud finder has enough battery power, as low battery power affects the reliability of the tool.”

Once checked, the next step is to calibrate the stud finder, continues Kerr, “Begin calibrating the machine by holding it against the wall, in an area you know doesn't already have a stud.”

He adds, “Once calibrated its a simple case of slowly scanning across the wall horizontally, making sure you don't lift it from the surface at any time. The device will then light up or beep when it detects the edge of a stud.”

Irving shares a few tips for moving the device: “To move the device, keep the stud finder as flat as possible and in full contact with the wall, slowly moving it horizontally.” He adds, “I recommend moving around 1-2 inches per second, as moving too quickly can reduce the sensor response time and may cause you to miss studs.”

Its important to identify both edges of the stud so you can get the centre. Timber studs are commonly 50mm x 100mm or 50 mm x 75mm, or slight variations on these sizes.

Paul Kerr

Paul Kerr is an experienced home building advisor for Beatsons Building Supplies with a demonstrated history of working in the retail and merchanting industry. Through Beatsons he has seen everything from outdoor patio organisation to rebuilds.

Using a magnetic stud finder

These are more basic than electronic stud finders and to start using one Irving suggests, “Begin by scanning in areas where fasteners are most likely to be present. This is likely to be near electrical switches, corners, vertically from the framework, and around 400mm from a known stud location.”

Start by placing it against the wall, then move it slowly horizontally. Keep your movements consistent. When it passes metal screws or nails, Iriving says it will, “cause a noticeable ‘pull’.”

Once you’ve found the screw, nail, or fastener, assume it's in the centre of the stud. You can gently tap with a hammer on either side. When it sounds hollow, you’ve passed the stud.

Irving adds some sage advice, “Remember that magnetic stud finders may be less effective if adhesive was used heavily in the wall. Additionally, if fasteners are deeply set, it will also make it harder to find studs."

Common stud finder mistakes to avoid

It’s easy to assume that a stud finder will work without too much trouble, but there are mistakes to avoid to get the best from it. Irving says, “Most typical errors that arise from stud finders are misuse, incorrect interpretations or the failure to cross-verify any findings.”

Kerr points out the biggest issue: “The main problems arise from a lack of proper calibration; you need to give it time to properly assess the depth of your wall.” Irving adds, “I always recommend double-checking that an electronic stud finder has been calibrated correctly before use, as this is a likely issue for a false negative.”

Another common mistake is moving a stud finder too quickly, shares Kerr, “You want to avoid moving too fast or haphazardly across the wall, as this can lead to mistakes.”

Irving says, “Ensure the finders are flat against the wall with no tilting, and always make sure you identify both edges of the stud, as failure to do so could result in missing the stud entirely.”

Kerr points out that false positives are a common mistake DIYers make. To stop this happening, he says, “Pay attention to clues within the walls (radiators, sockets, boilers, etc.) so you don't accidentally pick up pipes or cables with the scanner.”

Irving shares how to avoid cables: “Electrical cables are most likely found vertically or horizontally from sockets and switches, and directly above any electrical accessories.”

To ensure an accurate reading, Irving suggests double-checking a wall, “Once you believe you are finished with your findings, double-check and then check again to be as safe and accurate as possible.”

FAQs

How far apart are studs in a wall in the UK?

Knowing how far apart the studs in a wall are helps determine where other studs are located. Irving points out, “In the UK, timber wall studs tend to be around 400mm or 600mm centres.” He adds, “400mm centres tend to be the most common spacing in the UK, as they are the most compatible with 9.5mm plasterboard.“

However, 600mm centres are common elsewhere, says Irving, “600mm centres are typically used in timber frame construction as they require thicker plasterboard.” Kerr adds a note of caution, “UK studs are usually placed around 400mm apart, though this depends on the age of the house; older houses can differ.”

One simple tip is to locate the centre of the first stud, the next stud along and measure. If the distance is 400mm, the centre of the next stud should be 400mm.

How reliable are stud finders?

Stud finders have an important job, so it's important they are reliable. Paul Kerr says, “Electronic and magnetic stud finders are usually very reliable, around 70%-90% reliable in fact.”

However, Irving says, they are not perfect. “Their accuracy depends on the type of stud finder used, the wall's construction, and ensuring the finder is calibrated before use.”

Kerr continues, “Magnetic scanners are pretty much perfectly reliable at picking up screws and nails in studs. It usually comes down to making sure you don't pick up other items in the wall.”

He adds, “For best practice, you can use an electronic stud finder to find an approximate stud, and use the magnetic scanner to pinpoint nails and screws within the stud to confirm it.”

A stud finder is an essential tool for finding studs in a wall. So if you have some smart kitchen shelving ideas or wall panelling ideas, make sure to use the stud finder. If you are building a partition wall makes sure to set the studs 400mm or 600mm apart. This will make it much easier to find them later.