3 Reasons Your Stud Finder Might Not Be Working in Your Old Apartment

I recently moved to a new apartment — and when I say “new,” I actually mean “new to me.” Like many others across the country, I’m actually living in a pretty old building (called “pre-war” here in New York City). I’m still in the process of decorating and nesting, and to save money (and build up my DIY skills), I’m trying to do as much as I can on my own without hiring a handyman.

That’s what led me to purchase this $9 stud finder on Amazon in hopes of confidently finding a stud in the wall to hang some things that I knew would need extra support (heavy planter hooks, a winter coat rack, large pictures, and more).

If you’re hanging heavy things like me, you have to secure them into a stud, which is a vertical wooden beam behind the wall that’s a part of the framework of the building. Studs are super sturdy, so you know that if you drill into them to mount, for example, a TV, then it will stay in place.

The stud finder works like this: It’s a simple device that beeps when you locate a stud as you slowly move across your wall. Well, it beeps when it locates something behind the wall, which is a problem when it comes to older apartments.

Every time I moved my stud finder across the wall, I would get different beeps in different spots. There seemed to be little consistency in where it was beeping, and in the end, I wasn’t ever able to locate a stud — which, you might remember, was the whole point of the stud finder. But after doing some research, I realized this is actually a common problem in older homes, so I reached out to Jordan and Barry of the Brownstone Boys (@brownstoneboys) in Brooklyn, New York for some insight. They specialize in restoring beautiful older homes, so I knew they’d understand my problem and help me get to the bottom of it.

Here’s what the Brownstone Boys say might have been setting off my stud finder:

“Many old homes have plaster over lath, which are small horizontal strips of wood nailed onto the studs and covered in plaster. The plaster is put on in layers and the thickness underneath can vary,” they say.

They explain that this messes with stud finder because the density can vary greatly, so it makes sense that the stud finder is confused by its findings.

The good news: “If you’re hanging something on the lighter side, you can probably just put a screw in the plaster,” they say. “Plaster is much thicker than drywall and there is wood lath behind it so a screw will probably hold.” Avoid nails, which can cause the plaster to crack and even crumble, and always pre-drill. For heavier items, use metal molly bolts that can get behind the lath.

“In a New York townhouse that has party walls between the buildings, they are almost always plaster over brick,” Jordan and Barry say. “So your stud finder will only find a solid brick wall!”

The good news: You can Pick up a masonry drill bit (these are different than your basic woodworking drill bits), pre-drill, and then put in a masonry screw. It will definitely be able to hold a heavy item.

This is the option that keeps me up at night! But Jordan and Barry say it’s much more likely to be the first two options — either thick plaster or plaster over brick — and you can use the process of elimination to determine if you’re trying to drill into a spot that you shouldn’t.

“If you can determine the wall isn’t brick and you don’t think it’s just thick plaster, try to figure out if there is a bathroom above where you are trying to drill,” they say. “Could it be a pipe? If so, you might want to move over a bit for obvious reasons!”

The Brownstone Boys say that a magnet or magnetic stud finder should detect the nails holding the lath to the studs if you’re dealing with plaster walls.

“Alternatively, you can always just look for an outlet or light switch that is likely connected to a stud,” they add. “If the wall is a party wall, or a wall that is shared with a neighboring building, knock on it. If it is very solid, likely it’s plaster over brick. In this case, no need for a stud finder because there are no studs!”

Jordan and Barry also note that if there isn’t a stud where you need one to be, a good heavy-duty wall anchor can hold up to 100 pounds — so you can still mount your TV with confidence, even without a stud.

DIYing in an older space can feel intimidating, but Jordan and Barry encourage me (and others) to just jump in.

“Sometimes you might need to get out the drill and make some holes. Don’t be afraid to do it,” they say. “Spend some time learning to patch them and you won’t be as afraid to start poking around!” 

And while plaster and brick walls may be annoying for stud (or no stud) locating, the charm and beauty that comes with decorating an older home make it more than worth it.