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Electrical Boxes 101 - Lighting, Ceiling Fan, Junction Boxes


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Junction Box
Electrical Boxes 101 - Lighting, Ceiling Fan, Junction Boxes

Junction Boxes are Typically Square Boxes

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Typical Size:
4" Square; 1-1/4"- 2-1/8" Deep


  • A junction box is an electrical box used to run multiple conductors in two or more directions to bring power to various electrical devices.
  • Junction boxes are required to be installed so they are always accessible;
  • Never install a junction box in a concealed wall or ceiling space where is can not be accessed in the future.
  • Wire connectors (wire nuts) and wire lengths take up a lot of space in a box. Because square boxes provide maximum volume for multiple conductors and connectors they are most often used as a junction box.

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