Stud finders and scanning tools are used to locate wires, pipes, pvc, rebar as well as both wooden and metal studs. These stud finders work by detecting density changes in the wall directly underneath the scanner. For wall surfaces that are thick or uneven, like you find with lathe-and-plaster or textured walls, you’ll need a more powerful scanner than for standard dry-wall / sheet-rock. Here we review professional grade stud finders / scanners including Franklin ProSensor 710+, Zircon MultiScanner i520 and Black & Decker BDL190S BullsEye.
For newer homes that are made with dry-wall, you can find standard commercial / residential grade stud finders for under $20 – see our recent review for recommendations.
There are also “tradesman / industry” grade scanners which use wide-band radar to scan almost anything, including asphalt, marble and concrete to a depth of 6 inches. These will cost from $300 to $800 (or more) – we reviewed the top devices in our article on pro-scanners.
Franklin Sensors ProSensor 710+
Operation is simple and straight-forward with one-step: just press the button and when placed on wall LED light show you an instant indicate of the studs location. The Franklin 710+ uses their patented “Triple Accuracy Technology” which analyzes and triangulates data from all the sensors for highest accuracy and deepest sensing depth in this category.
The “+” version has a built-in bubble level and ruler, which is an added bonus from the original “710”. The “710+” is also slightly smaller, making it easier to get a reading in tight spaces.
We also recommend getting the Hard Case for Franklin Sensors ProSensor 710+ Professional
Zircon MS i520
The Zircon’s MS i520 is a multi-surface scanner with 4 operational modes:
StudScan – Use this mode to find the center, edges, and direction of wood or metal studs up to 3/4 inches (19 millimeters) deep. For best results, always start in this mode when looking for studs
DeepScan – If Stud Scan mode provides irregular readings, or the Signal Strength Indicator is weak, the studs might be behind more than 3/4 inches (19 millimeters) of drywall. Slide the mode selector over one notch to switch into DeepScan mode. This doubles the scanning depth to 1-1/2 inches (38 millimeters) deep and allows for increased accuracy on deeper targets
Metal Mode – Metal Scan Mode Detects Both Ferrous and Non-Ferrous Metal. Use this mode to locate and avoid hazards such as pipes behind walls. Metal Scan mode detects non-ferrous metal such as copper pipe up to 1-1/2 inches (38 millimeters) deep, and ferrous metal such as rebar, up to 3 inches (76 milimeters) deep.
AC Scan – AC Scan Mode Helps Find and Track Live, Unshielded Wires. In this mode, the LCD screen finds live, unshielded, electrical wires up to 2 inches (51 millimeters) deep.
Some other nice features include:
- ACT (Auto Correcting Technology) automatically corrects common user errors, such as when scanning begins over a stud
- Audio tone sounds beeps to indicate when a stud or wire is located
- Signal strength indicator helps to distinguish between shallow and deep targets
- SpotLite pointing system to give you a laser line for marking the edges, centers and wires
Depending on the material and construction of your walls, the Zircon may have some problems with first-pass measurements. To make sure you have a proper reading, you may need to scan back and forth a few times, marking on each pass. This issue was brought up to Zircon. The manufacturers have noted that “Due to irregularities in plaster thickness, it is difficult for the MultiScanner i520 to locate studs in StudScan and DeepScan modes. Change to Metal Scan mode to locate the nail heads holding wood lath to the studs. If the plaster has metal mesh reinforcement, MultiScanner i520 may be unable to detect studs through that material”
You will need to provide your own 9V battery.
Buy one on Amazon, Zircon MultiScanner i520 Electronic Wall Scanner
Black & Decker BDL190S
A final note regarding stud sensor apps for your smartphone. There are many of these for both iOS and Android devices, ranging in price from free to about $5. These may work, and for free they may be worth trying if you are in a bind. (Make sure you aren’t giving up too much personal data when using a free app – read the Best 3 Tips To Protect Your Privacy ).
The basic principle behind how these apps work is that they monitor disruptions / variations in the magnetic compass readings in the smartphone sensors. The sensors aren’t precise, and if there aren’t a lot of metal nail heads / screws in the wall you won’t get a very good reading. For thicker walls with texture or plaster, these vary from very poor accuracy to not accurate at all.