NM cable is common in households and commercial spaces for their multipurpose uses. Different states have different electrical codes regarding wiring and the use of cables. You will see the benefit of using Romex® brand NM cable in drop ceilings, but is this the right thing to do so?
Today we answer what you can do.
Can you run Romex in a drop ceiling?
You can run Romex® brand NM cable in a drop ceiling. As stated by the National Electrical Code NEC, you can run NM cable in only one- or two-family dwelling units. For this, make sure you follow all the NM cable rules. Maintaining the maximum safety measures and sustainability should comply with NEC rules.
There is much confusion regarding the proper installation of a non-metallic (NM) cable in the drop ceiling. Some argue that it is not recommended and does not comply with NEC. In contrast, others say that there are some exceptions.
Romex® brand NM cable, just lying on the drop ceiling, is labeled as exposed by some people. The risk of exposed wirings on the drop ceiling is prone to damages.
The wire could be simply damaged by running drills on the ceiling or cutting off holes. The cable could easily be punctured in the process of adding supports or mounting. Thus, you can easily understand the risk it imposes.
Therefore, it is suggested to use running boards for Romex® brand NM cables in the drop ceilings. One thing to remember is that you should never use NM cables in joists. The Romex® brand NM cable is permissible in the accessible ceiling only. Running it in joists will impose more significant threats.
While some forums about wire maintenance say that there is not enough information given on the NEC about non-metallic (NM) cable. The standard agreement is achieved by discussions by professionals.
NM cables lying on the suspended ceiling are not really exposed as the wire is not easily accessible. It is beyond ordinary human reach, and it imposes shallow risk.
The only risk is the risk of damaging the wiring from drilling or hammering screws. But it only applies for 1-2 family dwelling units.
For commercial spaces, you would have to change the whole design if any structural change occurs. That is a discussion for another topic.
Three reasons why you can run Romex® NM cables in a drop ceiling
Running Romex® brand NM cables in suspended ceilings could be tricky as there is no direct guide prohibiting this practice. Various comments in the electrical forums do not find it risky as the wires are not exposed.
Below we discuss why you can run Romex® NM cable in a drop ceiling.
Dwelling places:
NEC approves installing NM cables in the drop ceiling of dwelling places that do not hold more than two families.
Romex® brand NM cables or other NM cables can be used in construction types 3, 4, and 5, up to 5 stories tall. The structures would have to be commercial or residential.
Electric conduits are not mandatory, but they will provide extra safety in buildings that are more than 2 stories tall.
Out of reach or exposure:
As the drop ceiling is out of reach of so it is considered fairly safe if NM cable lay there. But you have to be careful next time operating with drop ceilings.
Unlike commercial places, there is no need to change the infrastructure in family dwelling places; therefore, running Romex® brand NM cables in suspended ceilings is safe.
Low voltage support wirings:
Power cables that are used to connect TVs, home stereo speakers, projectors, AC could be run in a drop ceiling. As regular electronics do not use that voltage, you can use NM cables.
How to run Romex® brand NM cables through the ceiling?
Running Romex® brand NM cables through the ceiling is no hard task. If you are uncomfortable with wiring projects, you should consult a professional electrician.
For the project, you will need the following materials.
- A small bullet level
- A keyhole saw
- A tape measure
- A stud finder
- An assistant
- A voltage tester
- A fish tape or flexible curtain rod
- A cordless drill
But before starting, you should check with local building inspectors to ensure compliance with local codes. It would be best to plan out a map of the wiring you will do.
Determine the length of the cable and buy some extra to be safe.
Before doing any electrical work, you should always turn off the electricity. Find the circuit breaker in your place and turn off the lever from where power is drawn.
Mark the entry spot and exit spot:
Before passing the wire, make a plan of where the entry point and exit point of the wire will be. If the exit point is in the wall, you will have to use a stud finder to not cut through studs.
If the exit point is through the ceiling, mark the point and then use a drill and keyhole saw to make space for wiring.
If you are planning to include switches, use the bullet level to level the switch box and use a pencil or sharpie to mark the edges.
Running fish tape:
Insert the fish tape from the exit point to the direction of the entry point. After that, connect the wire to the fish tape and bring out the wire from your desired location.
Can Romex® brand NM cables be used above a drop ceiling?
Yes, Romex® NM cables can be used above a drop ceiling. Romex® brand NM cables are classified as nonmetallic sheathed cables. These cables are common in households and residential places.
NM cable is a typical scene in the drop ceilings among various family housings in the states. As long as the cables are not exposed to damage and comply with building codes, it is safe to use Romex® brand NM cables above a drop ceiling.
Dwelling or households approve Romex® brand NM cables, but places that allow access to drop ceiling cannot use it. Drop ceilings with no removable tiles or access panels may have NM cables above them.
Drop ceilings that are accessible may have Romex® brand NM cables with running boxes or conduits. Otherwise, it will be considered exposed. The exposed cable can be easily damaged and catch fire.
Whatever the use is, check with local building inspectors to make sure you comply with the local electrical codes.
When running cable through drop ceilings which type of cable do you need?
You can run a number of cables in drop ceilings—power cables for speakers, projectors, HDMI, and many more. Usually, wiring with low voltage is not an issue for drop ceilings.
How voltage power supply wirings require more attention. So there are specific rules set by NEC for that. Nonmetallic-sheathed cables are popular choices for drop ceilings. Below we discuss the three types of Nonmetallic sheathed cables.
Type NM:
This cable has a nonmetallic jacket with insulated conductors inside. You can use type NM cables in both exposed and concealed works. Dry locations are preferred for the use of such cables.
It can be installed in a masonry block.
Type NMC:
This cable has a corrosion-resistant nonmetallic jacket with insulated conductors inside.
You can use this cable in dry, moist, or damp locations. As it is corrosion-resistant, you can install it in corrosive areas. This cable works fine in both exposed and concealed works.
It can be installed inside and outside of the masonry block.
Type NMS:
This cable has a nonmetallic jacket with insulated power, control, and communications conductors inside.
This cable has a nonmetallic jacket with insulated conductors inside. You can use type NM cables in both exposed and concealed works. Dry locations are preferred for the use of such cables.
It can be installed in a masonry block.
However, some prohibitions should be followed accordingly. Make sure you follow local guidelines correctly. Hire a professional electrician if you are in doubt or uncomfortable around wirings.
Final Thoughts
Wirings could be pretty tricky given that you have to consider the amount of volt and ampere. Proper wiring will keep you and your loved ones safe. Romex® brand NM cable is easy to install and can be left exposed to some extent in the drop ceiling. But you should always contact a professional to be safe.