Is it Dangerous to run cables through a wall? The short answer is, well, probably not. It really depends on a few different things to determine whether it is dangerous or not.
And depending on how cables are run through the wall, it may also break the regulations within the NEC (national electric code). I’m not going to dive too deep into the NEC in this article. My main focus is to ensure you effectively and safely run cables throughout your home.
I also won’t be detailing how to wire an entire home, this is purely meant for someone who wants to add audio, video, or other equipment to their already built home. I’ve ran thousands of different cables throughout customers’ homes and businesses, and here are some of the methods and ideas I use when doing so.
Effectively and Safely Run Cables Through a Wall

There are some important things to remember when you want to safely run cables through a wall. You may want to just go for it! Cut two holes in your wall then feed the wire between them.
But come on, let’s be smart about what we are doing! We aren’t cavemen anymore, we’re in the 21st century, so let’s be smart and have a solid plan before doing anything.
- Know what is behind the wall before you run cables.
- Avoid running power cables inside walls!
- Avoid running cables next to electrical lines.
- You can run low voltage and other cables in bundles.
- Inspect your cables before you run them.
Know What is Behind the Wall Before You Run Cables

Before you go cutting any holes in your precious wall, figure out what is behind it first. Don’t just go tapping on the wall like a madman. Some people may suggest this method, but it’s fairly inconsistent unless you have a trained ear.
Get yourself a decent stud finder (on Amazon), it will be useful to safely run cables as well as for future projects. If you want a really nice stud finder, check out the ProSensor 710 (on Amazon). I used this one back when I used to do audio/video installations, and it works extremely well.
Use the stud finder in the area where you plan to run your cables. Note the distance between the studs, and any other out-of-the-ordinary readings. These random readings might be a small pipe, electrical wire, or maybe a misreading from the stud finder, depending on the type of wall and where it is located in the house.
Are there any studs running horizontally across the wall? These are called fireblocks. If there is a fireblock, use a flex bit to drill through it. This is recommended if the bottom access hole isn’t too close to the ground.
You can also cut out a piece of drywall that is directly over the fireblock, drill a hole through it, run your cable, and patch the hole back up. Both methods work very well, but cutting the drywall is definitely more work because you will need to mud the wall, sand, then repaint the area.
Avoid Running Power Cables Inside of Walls!

I would strongly suggest not running power cables through any walls. When I say power cables, I mean power cables for televisions, receivers, etc., not actual electrical wires (Romax).
It’s actually against article 400.8 in the NEC (National Electrical Code). You should not run power cables through a wall as a substitute for permanent wiring, ie wired outlets.
It can be done, but if a fire results from this, then the insurance company may find a reason to not cover the damages. If you want to safely run cables, and you need to get power to your television or other devices but need an outlet.
Then hire an electrician to professionally install a new outlet. Or you can use a simple device called a Power Bridge (on Amazon) to install a semi-permanent outlet yourself (it coincides with NEC regulations and is safe to use).
Or if you actually know what you are doing, install a real outlet yourself. Yes, it is a little more work, but it will be a much better method to safely run cables while still following the NEC regulations.
Avoid Running Cables Next to Electrical Lines
Low-voltage cables and electrical lines should not be close to each other. It can cause interference in the signals being sent to the electronics connected.
And any uninsulated contact between an electrical wire and a low-voltage cable can cause serious damage to the equipment or even a fire! It is suggested that you maintain at least 6 inches between electrical and low-voltage wiring.
However, most cables are shielded pretty well now, so an inch or so will probably be perfectly fine. Remember this also applies to light fixtures.
If you are running speaker wire to in-ceiling speakers, then make sure the wiring is an acceptable distance from the lighting fixture. Some lighting fixtures will produce a lot of EMI (electromagnetic interference) which can also cause issues with low-voltage cabling.
You Can Safely Run Low Voltage and Other Cables in Bundles
You can bundle low-voltage cables together when running them. This makes it much easier when running them through walls. As long as the cables are well insulated, there should be no interference between any of the signals.
Make sure you are using high-quality cables. If they are cheap cables, then you could run into problems with interference and other issues in the future.
Go ahead and spend a little extra on those cables to make sure you don’t have any issues in the future.
Inspect and Test Your Cables Before You Run Them
Don’t even think about running ragged and torn wires. Simply ensure the cables are in good condition before you run them through the wall. No cuts, tears, etc. Use clean, good-quality cables, and you should not have anything to worry about!
It’s also a great idea to test the cables before running them through the wall to ensure they actually work. This will give you the peace of mind that once you get the cables through the wall, you won’t have to pull a cable out because it’s not working.
Conclusion
It is perfectly safe to run most cables through a wall! Really, the only cable you absolutely should not run through a wall is a standard power cable that plugs into an outlet.
These cables will heat up more than most other cables. They can cause electrical fires if there is a cut or another issue with the cable or device. Install an electrical outlet where the devices are located and ease your worries.
Fred Overdorf
Tuesday 3rd of March 2020
I just want to run an extension cord (4”) straight through my clothes closet wall to get a 15 watt fluorescent light in there. Is that OK ?
Jonah Matthes
Tuesday 3rd of March 2020
Hi Fred,
If it is a standard outlet extension cable then this is technically a fire code violation. You can do it, but I wouldn't suggest it. Extension cables should never run behind or through a wall, period.