So you need to drill a hole in the wall. But how do you know there’s nothing back there?
If you don’t have blueprints to your home, you can never be 100% positive there’s nothing behind the drywall. But if you inspect the area for possible pipes and electrical work, and only drill a short distance into the wall, you can reduce the likelihood of hitting anything important.
Obviously, there’s a lot to talk about here, so lets dig in.
Note: This blog contains affiliate links. If you click and make a purchase, I may receive compensation (at no additional cost to you.)
What You Could Hit
Lets start with what’s actually in your wall. There are three main things:
- Studs – These are actually meant to be hit.
- Electrical Wires – These are bad to hit.
- Pipes – These are really, really bad to hit.
Given your house has wooden studs (most residential homes, although steel studs are slowly becoming more common in high rises,) studs are actually a tool you can use to hang heavy things.
Studs are made of wood, and many times you actually want to hit them.
Wood is soft, and if your drill goes into something behind the drywall without much pressure on your part, chances are, it’s a stud. If you remove your drill bit and see sawdust stuck to the bit, you almost certainly hit a stud.
(Sidenote: If you remove your drill bit and see plastic, it’s more likely you hit a pipe. That is… less than ideal. Go shut off the water and electricity to your house. Then keep reading.)
You can also double check you hit a stud by looking for more studs in either direction. Studs are usually found either 16″ or 24″ apart. If you find another stud-like thing either of those distances away, chances are you’ve found a stud.
Good news – electrical wires are actually a bit hard to hit, for a couple reasons. First off, electrical code requires that metal plates be placed in front of wires that go through studs.
Metal plates are hard to drill through, so if you hit something that your drill won’t penetrate, stop trying! Your drill should easily bite into wood and drywall. If it doesn’t, consider it a warning that you should stop drilling.
So, electrical wires going through studs are usually protected by metal plates. Obviously, this is more likely in newer construction, and is somewhat dependent on your house builder/electrician following code.
Secondly, electrical is wired so that there is a bit of “give” in the line, that way, if you need to move it or pull it out further later, you have some extra cord to work with.
Because of this, if you hit a bit of loose electrical wire, your drill will likely just brush it aside, not actually penetrate the wire.
However, despite these things, hitting electrical wire isn’t impossible. If it happens, you’ll know. You’ll get a nasty shock (it’s unlikely to kill you, but you’ll feel it,) and probably be a little freaked out.
Hitting electrical wires is bad. Hitting a pipe is an actual emergency.
Water is a house’s worst enemy. Wood? Rots with water contact. Drywall? Starts to mold. Carpet? Flooring? Literally every construction material ever? Water destroys them.
So, hitting a pipe is bad. My next question: Do you have copper pipes or PVC pipes?
One of these is much harder to drill through than the other. If you have copper pipes, you’re in good shape. While you can certainly hit a pipe, it’ll take a lot of force to actually drill a hole through it.
Once again, if you hit resistance, stop drilling. Resistance is your best warning when drilling into walls.
PVC pipes, on the other hand, are much more common in newer homes. Unfortunately, they’re also easier to drill through. You might not even realize you did it until you pull the drill bit out and see plastic (and maybe a lot of water.)
Note: You might not always see water. If you hit a drain pipe, that little bit of plastic might be all you notice until 3 months later, the whole house smells like sewage.
How to Avoid Hitting Things in Walls
Hitting a pipe seems bad, I know. But it’s actually really easy to avoid hitting things in walls.
I’ve been drilling into my walls for over 6 years. I’ve never hit a single thing (other than an intentional stud.) Here’s what I usually do:
1. Visually Inspect for Possible Obstructions
Obviously, you can’t actually look into the wall. If you could, we wouldn’t be here. But you can look around your home and take a pretty good guess if there’s going to be a pipe or electrical wire. Here are some things to look for:
- What’s on the other side of your wall? If there’s a sink or shower, there’s probably a pipe in that wall.
- What above above or below your wall? If you’re beneath a bathroom, a pipe might run up the wall.
- Is there an electrical outlet or light switch nearby? Wires run to those things, usually at the same level in the wall. Try drilling above or below that level instead.
- Is your wall interior or exterior? If you live somewhere that gets cold, usually pipes are located on interior walls, since it’s easier to keep them from freezing that way.
2. Prepare to Drill
Once you’ve determined your location, and you’re pretty sure you won’t hit anything important, there are two main things you should do before you start.
First off, locate the water shutoff to your house. Be sure you can operate it. Just in case. Same with the electricity.
Secondly, grab your drill bit, and put a little piece of masking tape on it about 5/8″ from the end. This will tell you where to stop drilling. 5/8″ should get you through 1/2″ drywall.
(This is a spade bit, not a twist drill bit, but you get the idea, right?)
Hitting pipes and electrical wire depends on actually drilling far into the wall. If you don’t drill past the drywall, you won’t hit anything important.
The masking tape is your measurement. When you hit the edge of the masking tape, stop drilling.
3. Drill to Your Masking Tape Mark
Slowly drill up to your masking tape mark. This should get you just through the drywall (if it doesn’t, you’re probably close enough that you can poke the drill bit through with your hand.)
Don’t drill past the masking tape mark!
Now you have a nice little hole in the wall. If you actually need to drill further (like into a stud,) you can stick a small drill bit into the hole, and confirm that it’s a stud in the wall, and not a pipe.
Also worth repeating: if for some reason you didn’t follow this, and drilled deeper than 5/8″ into the wall, and you’re hitting resistance, stop drilling. Resistance is your best warning before something bad happens.
You might be wondering about fancy detection units on the market. They exist, and they’re not that expensive. Feel free to buy one if it makes you feel better.
But that said, I’ve heard many instances of the tool detecting a “stud” and it turning out to be a pipe. That’s probably my worst nightmare.
I don’t have one. My masking tape method has always worked for me.