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Can You Put a Junction Box in a Wall? (Quick Answers)

Junction box is a very familiar name to the electricians, as well as the people who are thinking about putting electric connections to their house. It is a part that ensures safe and secure electricity flow throughout your house. 

Can you put a junction box in a wall?

This is a very essential part of wiring your house, protecting them from any kind of damage, preventing short circuits, and it keeping away from water, fire, or human contact. Placing the junction box inside the wall is against the standard building code. So, it is not recommended.

A junction box or electric switch box is also known to electricians who use it to enclose electric wirings inside your house. Generally, switches could be needed to be put anywhere inside the house and that requires complicated wiring lines. 

Electrical wires are usually connected to switches in different parts of the house while they are attached to the wall. And the wires of different connections come together in the junction box. 

It is a box that you can hide inside the wall in order to keep all the wiring connections in a place together as well as away from any sort of contact with humans, fire or water to prevent short circuits. 

A special reason why the junction box is needed to be put inside the wall is to protect your cable connections from any external contact. 

If the cable connection is left open in the house, it might catch fire due to a short circuit and it can spread to the furniture of the house. Again, if the cable connections are not properly sealed, anyone can be electrified. 

So, it is required to use a junction box to cover the wiring connections. Also, for some reason, the junction box should not be placed inside the wall again. Placing the junction box inside the wall is against the building code. 

It is a delusive and ineffective way, causing weakness to the building walls’ load capacity. Moreover, a junction box packed with various wires might rub off together resulting in an unwanted fire if not aligned properly. 

A simple mistake could cost you expensive damage and hassle to your living. So, it is highly recommended to avoid putting junction boxes inside a wall. But still, if you want to put it, you must follow the building code and proper procedure.

Can you bury an electrical junction box behind a wall? “inside a wall” 

You can bury an electrical junction box inside a wall to secure your wirings but it is not advised to do so. Burying junction boxes inside walls weakens the wall by decreasing the load capacity and creating space inside walls which makes it dangerous.

In addition to that, sometimes wires could rub off with each other when stacked together inside the junction box and cause fire from a short circuit, which is also a safety hazard.

When you bury the electrical junction inside or behind a wall, it remains hidden from view, resulting in unseen occurrences due to the lack of visibility inside the box. 

Can a junction box be hidden behind drywall? 

As per the United States electrical code, it has been mentioned that it should never be attempted to keep a junction box behind drywall

But if you want to place it behind drywall, it should have a continuous run of wire, where it could be accessible to any sort of addition, reduction, or repair of connection. 

The best solution is to put a cover over the junction box so that it could be accessed anytime.

Also, the problem with having a junction box behind the wall is, if your home is ever hit by a high-voltage surge, you might need to check all the junction boxes to ensure they are working properly. 

Why are hidden junction boxes bad?

There are plenty of reasons why hidden junction boxes are considered to be a bad decision for houses. The main issue is, it prevents inspecting the issues inside and makes the repair procedure very difficult to execute. 

Some of the reasons are discussed below: 

Difficult to locate:

Hidden junction boxes are difficult to locate as they are buried inside a wall. Sometimes, it is even difficult to keep track of all the junction boxes. 

For this, during a high-voltage surge, it might take a lot of time to locate and inspect all the junction boxes and repair them. 

Harder to evaluate:

During repair, the junction boxes become harder to evaluate. As they remain hidden inside the wall, you cannot inspect the issue with bare eyes, you have to break the plaster in order to inspect the issue and solve it. 

Sometimes, the stacked planless wiring makes it more difficult to find out the problematic wiring inside a junction box.

Safety hazard when drilling:

During installations of new household furniture or items, such as TV, photo frames, wall hangings, or similar kinds of stuff that need drilling, it creates a safety hazard for the boxes. It becomes difficult to find or avoid the boxes.

As a result, mistakenly drilling over a box or wiring could cause a short circuit in your house.

What is code for an electrical junction box?

In the US electrical code, it is mentioned to keep junction boxes accessible and the size of the box from which the wires will come out should be at least 12 inches. They cannot be covered with any type of surfacing, drywall, or blocking material. 

A junction box connects wires coming from different locations so it must have the wires aligned properly in order to conduct proper power supply and ensure easy repairing. 

It is also mentioned to leave at least six inches of extra wiring inside the junction box considering future connection purposes. 

Where should junction boxes be located?

The junction boxes are used to connect two or more wire connections ending up to an outlet, light fixture, or switchboard. Depending on planning and design, they might extend to various accessory fixtures. 

The inspection and repair procedure might consume a lot of time and money if the junction boxes are hidden. So, it is advised to keep the junction boxes covered, so that they can be removed to inspect any sort of damages. 

Some of the easy ways to locate junction boxes are mentioned below: 

Wiring Diagram:

If you can manage to get the electrical wiring plan or the diagram for your apartment or house, you can easily get access to the junction boxes located in your house. 

The “J” in the diagrams refers to the junction boxes in the drawing. So, it is a very simple idea to manage the wiring diagram to locate the junction boxes.

Walls near heavy equipment:

Generally, in warehouses or factories, where heavy machinery is used, junction boxes can easily be found beside or around the machinery. In a warehouse, you can look around the compressors, pumps, or generators.

Inside cabinets:

Considering residential purposes, junction boxes can be found inside cabinets. That makes them covered and easy to access for a mechanic. Take a look at the kitchen cabinets or store room cabinets to easily find the junction boxes.

How to install a junction box in a wall?

It is better to get this job done by a skilled mechanic as electric wirings are sensitive, need proper alignment and connection sealing to prevent any type of damage. When installing a junction box, some criteria are required to install it. 

It is important to choose the right size of the junction box based on the wirings needed. Also, you will need a screwdriver, hammers, pliers, drill, etc.

The process to install a junction box in a wall is mentioned below: 

Place the junction box:

Decide a place where it is safe to mount the box. Make sure your wires have space for some extra inches inside the box. The box must be kept away from water, fire, and reach of human contact. 

Once you’ve decided, drill the wall and mount the box by screwing them up tightly.

Join the wires:

Once you have placed the box, Bring the wires inside the box from the wiring line. Keep at least 6 inches extra for both the wire ends. Separate the cover of the wires and twist the metal parts to ensure proper connection.

Fold and seal the wires:

Now that you’ve established the connection between two wires, it is important to seal them or they might get in contact with some other wire and catch fire. So, seal them using caps or electrical tapes.

Final Thoughts

It is possible to put a junction box behind a wall yet highly recommended not to do so as it violates the building code and standards. Putting junction boxes behind the walls makes it difficult to access and a safety hazard. So, it must be placed in a place where it can be accessible for repair.