If you need to find a stud in your walls (and you eventually will), we recommend the Magic Stud Finder Plus. It’s reliable and accurate, and because it’s magnet-based, it doesn’t need batteries or any kind of calibration. Unlike other stud finders, the Magic Stud Finder Plus allows you to mark multiple points on your wall without having to use a pencil. Because locating studs isn’t an exact science and to do it accurately, you need to double and triple-check your work, this is a feature that elevates it above the rest.
My experience with construction and home improvement
I’ve been in construction for 10 years and have been writing about tools and gear for the past six. In that time, I’ve used all kinds of stud finders and have nearly mastered the art of locating one by tapping a knuckle on the wall. I’ve also managed to pick up a wide variety of stud locating tricks, mostly from grizzled old carpenters.
Why use a stud finder?
There are a lot of reasons why you would need to find a stud in your walls. The most common is if you’re trying to hang something heavy like a large mirror. You could also be installing a pot rack or maybe an anti-tip bracket for a tall bookshelf. In all of these instances, it’s possible to use some kind of wall anchor, but if you really want to feel secure in the stability of your work it’s smart to screw directly into a stud. To locate one, you’ll need a stud finder. And to properly use a stud finder, it helps to know a bit of basic information about how your house’s walls are (most likely) built.
Basic wall construction
A standard framed wall is made up of horizontal pieces at the top and bottom (plates) and the vertical members that connect them (studs). Most framing is done with 2 x 4s or 2 x 6s, which are 1½ inches wide (they used to be 2 inches, thus the name). For the most part, studs are placed 16 inches on-center, leaving 14½ inches of clear space between the studs (this area is referred to as the stud bay). Some new construction is done with 2-foot on-center spacing, but it is not that common. Older houses can be a mixed bag. My own house, built in the early 1900s, has framing that is anywhere between 16 to 30 inches on center. It also has true dimension 2-inch studs. So it’s good to know the basics as a guideline, but you never know what exactly you’re going to find.
In most post-1960 construction, the wall surface is made up of sheets of ½-inch thick sheetrock or blueboard that are screwed directly the studs. To finish a sheetrock wall, the screw heads and seams are filled in and smoothed over with joint compound. A blueboard wall is entirely covered with a skim coat of plaster, usually about ⅛-inch thick.
Previous to 1960, either wood or metal lath was nailed to the studs and plaster was applied on top. The lath served the purpose of providing a backer to hold the plaster and lock it in place. In this type of construction, the plaster is much thicker and can be anywhere from ½ to 1 inch thick.
How to use a stud finder
To do this sort of double-checking with a stud finder, you need to locate multiple points and cross-reference them against one another until you’re sure you know exactly where the studs are. If you get a hit with the stud finder, check above it and below it to try to get other hits that are in a direct plumb line with the first (it’s typical for screws to be about 8 to 10 inches apart on sheetrock). Then check to the right and left of it and try to find more screw heads at the 16-inch mark (remember, common framing is done 16 inches apart). With a normal stud finder, this process means putting quite a few marks on your wall either with a pencil or little pieces of blue tape. The stud finder we’re recommending lets you leave non-marking magnetic markers on the wall for you so you don’t have to mar your paint job.
There are two different types of stud finders for home use: electronic and magnetic. We prefer the simpler magnetic type because they’re cheaper and more reliable1. A reliable electronic finder will run you north of $50—too much to pay for something you only use a few times a year, if that. A good magnetic one, like our pick, can be had for less than $20.
Magnetic finders are attracted the metal fasteners that hold the sheetrock or blueboard to your studs. If you find the screw, you’ve found the stud. Simple.
But even magnetic stud finders aren’t perfect. While they work great for sheetrock and blueboard, they are less effective on plastered walls because of the thick coat of plaster. About ½” of total thickness seems to be the upper limit of detection for most magnetic stud finders. But there is a work around for these thick walls. Because baseboard is nailed into studs, all you have to do is scan that for nail heads and you’ve found the stud.
How we picked
Once we narrowed it down to magnetic stud finders, I checked out all of the major online retailers (Amazon, Home Depot, Lowes, Ace, Walmart, Menards) and decided on five models to test out of the 10 or so that are widely available. I read all of the reviews I could (there aren’t many) and noted which finders were recommended at the contractor message boards. I also got a sense of each unit’s success by reading the user reviews at Amazon. Both Amazon and the message boards need to be taken with a grain of salt, but I was able to isolate some consistencies about how well each one worked. With one exception, I opted for units that offered additional features like level vials, an audible detection sound and removable magnets. The ones we tested were the CH Hanson Stud4Sure, Magic Stud Finder, Stud Thud, Johnson 160 Stud Finder Plus and the Rev-A-Lock2 .
How did we test?
For testing, I used all of the finders to locate studs in various rooms of my house. I have portions that consist of sheetrock and joint compound and other parts that are blueboard with a skim coat of plaster. These two conditions (prevalent in post-1960 construction) don’t pose a high level of difficulty for the finders because at most the screwheads are only about ⅛” below the surface of the wall. But not everyone has a house built after 1960.
To simulate the thicker plaster on lath wall, I took a piece of ½-inch sheetrock and held a screw head to one side while I scanned the other side with the stud finders. Then I incrementally backed off the screw head, as if the wall were thicker. It’s my experience that ½” to ⅞” is a good range of plaster thickness. When I gutted my hundred year old farmhouse, the horsehair plaster averaged about ½”.
The way the Magic Stud Finder Plus works is that the underside of the body has two cut-outs where the little magnetic targets fit. When the unit is being used, the targets are captured between the body of the tool and the wall that is being scanned. When it moves over a metal screw head, the targets click and stick onto the wall where they stay as you remove the body of the finder. Then, you can load another target and locate another screw head. Once that one is placed, you can do it a third time (the set comes with three targets, and additional ones are available standalone in case you lose some or need more). When all of the targets are on the wall, it’s easy to trap one of them with the body and slide it to a new location. So you can first check vertically, then horizontally. Using the Magic Stud Finder, I was able to get a firm understanding of the framing layout of an entire wall in well under a minute. Here is a video that I found of the tool in action.
Using these targets is way easier than making little marks on a freshly painted wall (which is when a lot of mirror hanging or shelf installation might take place). The Magic Stud Finder Plus was also the only finder with felt pads on the back of the body, which is another nice touch and will protect your walls as you drag it around. The body also has level and plumb level vials.
So the magnets are all a bust when it comes to deeper scanning on older walls. But as mentioned earlier, the workaround for this is that you can find the nails in the baseboard which should be driven into the studs. You still should check to the right and left for a consistent 16 or 24-inch pattern to confirm. There are also a number of other tricks that I’ll get to in a bit that you can combine with this to increase your chances of success.
A DIY option
If you’re the crafty type, it’s not a lot of work to make a magnetic stud finder yourself. After all, it’s basically just a magnet. Instructables has a tutorial on how to make a magnetic stud finder, which consists of tying a piece of dental floss around a magnet. That’s it. There’s something to be said for the ergonomics and the built-in level vials of the manufactured ones, but if you’re in a pinch or if you just like making stuff, then there’s no reason you can’t use any old magnet as long as it’s strong enough.
The CH Hanson Stud4Sure is a popular item (1,000 five-star reviews at Amazon and counting) but because it’s just a magnet, it can only find one screw head at a time and nothing more. That means that you’ll need to mark up the wall in order to locate more than one point. The Stud4Sure’s magnet is stronger than the ones in the Magic Stud Finder’s targets, but this added strength doesn’t really matter because all of the magnetic stud finders can detect a screw head through a skim coat of plaster or a layer of joint compound. The Stud4Sure could just barely locate metal through the ½-inch sheetrock simulating a thin plaster on lath wall, but had trouble going any deeper.
What the Stud4Sure really has going for it is durability. It was the only unit that I tested that looks like it could really withstand a beat down. The others are all cheaper plastic and look fairly fragile. This shouldn’t matter much for someone hanging a mirror, but to a contractor or carpenter this is important.
The other finders were basically all just magnets and little more. The Stud Thud made a noise when it found metal and the Johnson magnet pivots on a center point like a dowsing rod. The Rev-A-Lok didn’t prove to be any stronger than the rest. With all of these simple magnets, you’ll be marking up your wall trying to find a stud.
An interesting spin on the magnetic stud finder is the Shinwa 78610. This tool is cylindrical, like a pen, and it combines magnetic detection with a needle probe. Once you locate the fastener in the wall, you can send the needle in to confirm you’ve hit a stud. The needle has a built-in depth gauge, so it also tells you how thick your wall is. The tool received a positive review from Make Magazine and the Amazon feedback is all glowing as well. The Shinwa still requires you to manually mark your walls, and for most newer construction, it’s a given that your walls are going to be about ½” thick, so in many cases, the needle won’t be needed. There’s also the added inconvenience of putting little holes in your wall, but the review at Make has an image of the puncture, and it is quite small.
The Franklin ProSensor 710 ($50) also deserves a mention. It’s a stud finder that was released a few years ago to extremely positive reviews (here, here, here, and here just to name a few). Unlike other electronic sensors, the Franklin simultaneously scans 13 different points. Through the corresponding 13 LED lights, the sensor can show you the exact width of the stud, indicating both edges at the same time. Other stud finders can only locate one point at a time, so it can be a fishing expedition to confirm both sides. The Franklin is a pricey item, but in a few short years it seems to have solidified its reputation in the remodeling industry. But it’s too expensive unless you need to find studs all the time.
The Milwaukee Sub Scanner and the Bosch D-Tect are representative of the higher end of professional-level wall detection. These tools are capable of deep scans that can locate rebar in concrete at a depth of up to six inches. They can pick up live electrical wires and differentiate between ferrous and non-ferrous metal, meaning they can isolate copper pipes. Because of the price and the amount of functionality that exceeds the homeowner’s need, these aren’t practical tools for hanging pictures. The Milwaukee is in the $160 range and the Bosch (with more advanced capabilities and a much better visual display) is around $675.
Another type of wall detection tool that is worth a mention is the CL10 made by General Tools. It’s a two part system that can be used to locate wires and pipes in a wall (but not studs). One piece, the transmitter, sends a frequency through a wire or pipe while the other piece scans the wall like an electronic stud finder and visually displays the location of the frequency. The receiver can pick up the signal from a distance of over six feet. At $200, the CL10 is out of the range of general use.
The old tricks
Beyond electronic and magnetic stud finders there is also the old-fashioned method of rapping your knuckle against the wall and listening for when the hollow sound shifts over to a solid thunk. Another crafty way to do it is to shine a flashlight down the wall and look for slight vertical ridges that indicate the studs. This doesn’t work well with plastered walls, but if you’ve got sheetrock and joint compound, you’re likely to have success.
Another trick is based on the fact that electricians are usually right-handed, so electrical boxes tend to be mounted to the right of a stud. Which brings me to another good move, which is to remove the cover of an outlet and see if you can tell which side the stud is on. Then measure your 16 inches from that point.
It’s a good idea to have a stud finder kicking around the kitchen drawer, but there’s no need for it to be a high-end piece of tech. A simple magnet-based stud finder combined with a little knowledge of traditional wall framing should do the trick in most situations. It’s not an exact science, so you’ll need to double and triple-check your findings. That’s why the Magic Stud Finder Plus is so valuable. The fact that it lets you leave magnetic targets on the wall makes it very easy to confirm where the studs are located.