An electrical box, also known as an electrical enclosure, is used to house and protect the wires and cables connected to your home or office.
These boxes can be made of different materials, such as wood or metal, and they come in various shapes and sizes to fit the area where they are installed.
If you’re looking to install new wiring in your home or office but aren’t sure which type of electrical box to get, read on to learn more about some of the most common different types of electrical boxes available today.
What Are Electric Boxes?
Electrical boxes are essential components of your home’s electrical system that protect wire connections from short circuits.
However, the wide variety of boxes can be perplexing for many DIYers.
Plastic and metal boxes are available, as well as “new work” and “old work” boxes, round, square, and octagonal boxes, and boxes with load ratings for ceiling fans and heavy light fixtures.
The most commonly used boxes for home wiring projects are available at home centers and large hardware stores, but knowing the differences is critical to purchasing the correct boxes.
There are several options to consider, such as materials, shape, and size. We’ll go over the different types of electrical boxes you should know in this section.
Different Types of Electrical Boxes
1. Standard (Single Gang)
Standard boxes are used for single light switches, toggles, duplex outlets, thermostats, and other devices that require a single opening.
These boxes measure about 2 deep (although not all have a back) by about 1-1/4 wide.
These different types of electric boxes come in several styles, including blank (no knockouts), combination (combination switch/outlet box), double combo (duplex outlet plus switch box), double blank (two blank plates side by side with no knockout openings on either plate), with knockout plugs (knockout openings on both plates).
Knockout plugs are handy when installing a large grommet or conduit connector into an electrical box—something that is often easier done before you mount it on your wall.
2. Extended (Double Gang)
These are used for larger devices such as heaters, air conditioners, or other appliances that require a more prominent service entrance point.
These are available in 120-volt and 240-volt configurations. When using a 120-volt appliance, use both receptacles (or breakers), or it may overheat.
These different types of electric boxes are commonly found in bathrooms or kitchens.
The top outlet can be switched on or off by flipping a switch inside your home’s breaker box, and the bottom outlet always remains on.
Some homeowners install additional lights above their sinks to illuminate countertops while cooking at night without turning on overhead lights and wasting energy.
You can also wire the bottom outlet directly into your home’s main electrical panel, so you don’t have to flip any switches when you want power—plug something into either receptacle!
If you plan on running an extension cord out from your house, choose an outdoor-rated cable with three prongs that can fit into either opening and then connect two-pronged plugs to each end for easy setup!
3. Large (Flush Mount or Surface Mount)
This rectangular or square-shaped box lets you mount your electrical panel on a wall or surface (either flush with the wall or stick out).
Large boxes come in two sizes: 2 deep for 15-amp breakers and 4 deep for 20-amp breakers.
It’s important to know which size you need because these different types of electric boxes are not interchangeable; if you accidentally buy a smaller box, there’s nothing wrong with using it, but you’ll need to get another one if/when you upgrade your panel.
You can also install switches and receptacles in large boxes as junction boxes.
However, it would help if you were careful about how many devices you connect to each circuit breaker; overloading a circuit can cause overheating and fire hazards.
If possible, run new circuits rather than add more existing devices.
4. Mid-Sized (Side Mount)
A mid-sized electrical box is commonly used for single switches, small junction boxes, faceplates, security systems, and phone jacks.
These are easily mounted on wood studs and usually do not have any knockouts (holes) in them.
The exception is if you will use them to house a device or receptacle that needs to be fed from two sides with individual wire pairs.
You might find one knockout on each side for feeding into your wallboard when appropriately wired.
But remember that if there is only one knockout, it does require cutting one set of wires completely to access it for wiring purposes.
5. Recessed or Ceiling Mount
They’re often used in areas with no outlet or a surface that you can drill into and mount on either side of a wall, projecting out toward you.
They can also be built into ceiling tiles or angled to fit over existing structures like a roof peak.
These are often used when there isn’t enough clearance above an area to work with, and they’re much less invasive than surface mounts, so they work well in homes or offices.
But remember: If you don’t plan your installation carefully (knowing what else will be mounted in an area).
These boxes can block access for additional equipment down the line—so it’s always good to consult with an electrician before deciding on a recessed box.
Factors to Consider
The different types of electric boxes are available in various shapes, sizes, and configurations.
The different types of electrical boxes serve different purposes. While there is no right or wrong way to pick an electrical box, it is essential to consider how you will use it to make an informed decision.
Think about these factors before choosing an electric box. These questions are all things that can affect your choice.
Space
- Where will your box go?
- Will it fit into your home’s architecture?
- Will you need to install any additional supports?
Materials
- How much do you want to spend on each box?
- What materials do you want your box made out of?
- This will help determine what type of material best suits your needs.
Functionality
- Do you need a specific feature that might not be present in every type of electric box?
If so, consider which options have those features before deciding on the different types of electric boxes to use.
Tips on How to Install Electric Boxes
Installing an electrical box requires a few tools, including a stud finder and a measuring tape.
If you’re installing boxes for new wiring, you’ll need to know what size screws to use for each wire.
Be sure to shut off your home’s power before starting any electrical work! The first step is determining what size box your wires will need by estimating how many holes you’ll need.
Then, make your marks on either side of where it will go (remember to leave enough room for some wire). Next, drill holes a bit slightly smaller than your wires.
Please make sure they are level with one another! Insert them carefully, screw down their connectors, and cover them with wire nuts.
Conclusion
Installing electrical outlets and switches is a typical DIY project that most homeowners will face at some point.
With so many different types of electric boxes available, you’ll need to know which one to choose for your next project.
Not all electrical boxes are created equal, so it’s essential to ensure you’re getting a quality product before hitting your local hardware store.
