The connection points of all household appliances and devices go into what are known as electrical boxes. These boxes are found around your home and serve two purposes. The first is to provide a place where all electrical cables and devices are mounted and to provide a place where all wiring connections are protected from external factors.
With an electrical terminal box, you have both you and the wiring of your household appliances protected as well as a place that has all of the wiring organised. Electrical boxes make it easy for electricians to access the wiring of appliances and they are found in every household since they are mandatory. But since there are different kinds of places where you can have an electrical box installed there are different types of electrical boxes too.
Types of Electrical Boxes
Rectangular
The industry standard of electrical boxes are rectangular electrical boxes that can house single light fixture switches and outlet receptacles. These electrical boxes are known as single-gang or one gang boxes and they are usually 5 cm x 7 cm. The depth of a proper rectangular cable termination box ranges anywhere from 4 cm to 9 cm. There are also variations of rectangular electrical boxes with detachable sides which allow you to link multiple boxes together.
Plastic
With a plastic electrical box, you can use only non-metallic cables. They are more affordable than their metal counterparts and they are also not as conductive. Plastic electrical boxes are usually made of PVC or fibreglass.
Metal
If you want an electrical terminal box that will be able to house both metallic and non-metallic cables then go for metal electrical boxes. While metal electrical boxes are more conductive, meaning not as safe as plastic ones they can be ideal when you need to run a metal conduit to an electrical box.
Round Pan
Also known as a pancake electrical box is a 1 cm or 2 cm deep box which is mainly used for wall-mounted or ceiling-mounted light fixtures. These fixtures cannot weigh more than 20 kg otherwise you’d need to use a different kind of electrical box.
Ceiling Fan Rated
If you want an electrical box that can hold up light fixtures that weigh more than 20 kg then you should consider getting a ceiling fan rated electrical box. While your light fixture may not have a ceiling fan included with it this type of electrical box will be suitable for it. There are other versions of ceiling fan rated electrical boxes including a pancake version which are usually 1 cm deep.
There are also others that are about 5 cm deep which are the standard version of ceiling fan rated boxes. The majority of ceiling fan electrical boxes can hold light fixtures that weigh up to 35 kg. These electrical boxes can be mounted either directly (using four screws) or to a wood blocking or ceiling joist. Some ceiling fan rated electrical boxes can be attached to adjustable braces that span between ceiling joints.
Octagon & Round
Round and octagon electrical boxes can be put in the same category as they both come available with a depth range between 4 cm and 7 cm. They are also rated for mounted light fixtures that weigh up to 20 kg. Round and octagon electrical boxes are able to provide more room for wiring than round pan boxes and can be used as junction cable boxes too.
Junction
Talking about junction boxes, they are known as the standard electrical box and to be fair junction boxes is a far more popular term than electrical boxes is. Junction boxes are 10 cm square boxes that offer a lot of space making them ideal for wiring connections. The thing with a junction box is that it always has to be installed where they are easily accessible. A junction box should never be installed hidden in a ceiling space or wall.
Outdoor
An outdoor electrical box or what is also known as a weatherproof electrical box is one that is made from high-impact PVC or aluminium. These electrical boxes are usually mounted on exterior walls, decks, and roof overhangs. Outdoor electrical boxes should always have an outdoor fixture rated cover that is safe to use in damp or wet locations.
Gang Boxes
Since there are single-gang rectangular boxes there are also double-gang three-gang and even 4-gang boxes. These electrical boxes are oversized versions of standard rectangular electrical boxes. This means you can have two, three and even four devices can be mounted side to side. Some gang boxes come with built-in cable clamps. Remember the same gang design can be recreated with standard rectangular boxes by just joining as many as you want to form either a two, three or four gang cable termination box.
Box Extenders
A box extender is essential an electrical box without the back. You can look at box extenders as empty electrical boxes as they still are shaped as which are used to expand the capacity of an existing electrical box. Box extenders are installed on top of the electrical box flush with the drywall or the surface of any other material you have an electrical box embedded in unless it’s a junction box.
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