Identify the circuit and switch off the power to the wall. Unscrew faceplates, disconnect wires, and remove outlets or switches. Removing an old electrical box from a wall can be a daunting task. Even if you're confident in your DIY skills, you should always consult a professional electrician. I show how I took off the original electrical box, referred to as new work electrical box, from a wall so I could upgrade it to a double gang old work box to handle an additional switch for the fan in the bathroom. (Many of the links in this article redirect to a specific reviewed product.
[pdf] - **Switch box**: The thickness of the steel plate of the box body shall not be less than 1. Select enclosure type, material. This guide provides a complete overview of common steel plate thicknesses — from 1/4 inch steel plate to 12 inch steel plate — including typical grades, weight references, inch–millimeter conversions, and application examples for different industries.
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