Why Are Some Outlets Installed Upside Down?

Why are some outlets installed upside down?

This is one of the most common questions we receive during and after our home inspections.  Most electrical outlets in a home are installed with the two posts on the top and the grounding pin on the bottom.  On newer homes, you may notice that a random electrical outlet is installed upside down with the grounding pin on the top and you may wonder why this was done.  Your first thought may be that the electrician just accidentally did that.  But there is a specific reason this was done.

While there is no requirement within the standard electrical building code for the orientation of electrical outlets, it is a best practice to install them with the grounding pin on the bottom.  But another best practice is to install an outlet that is controlled by a wall switch to be installed upside down with the grounding pin facing up.  This standard install practice is used to designate which outlet is controlled by a wall switch.  And typically only one-half of the outlet is actually controlled by the switch.  So you likely need a lamp or some other electrical device you can plug into the outlet and try each half of the outlet to determine which half is controlled by the wall switch.

Building Code References

As home inspectors, we do not inspect to code but we are informed by the code.  The National Electric Code (NEC) regulates how electricians work and the requirements for installation of electrical devices and components.  NEC Section 210.70 discusses lighting outlets and specifically states:

210.70(A)(1) Habitable Rooms. At least one wall switch–controlled lighting outlet shall be installed in every habitable room, kitchen, and bathroom.  Exception No. 1: In other than kitchens and bathrooms, one or more receptacles controlled by a wall switch are permitted instead of lighting outlets.

To summarize this – every room must have either a light fixture that is controlled by a wall switch or have an outlet controlled by a wall switch.  And the best practice installation method is to install the outlet upside down that is controlled by the wall switch. We often see new construction homes with bedrooms and living rooms that have wall outlets installed this way and we will then test that outlet with a plug-in outlet tester to verify that the wall switch nearby controls that outlet.

Most home inspectors will document this condition in their reports to validate that the wall switch properly controlled the upside down wall outlet.  Since each room needs to have a light fixture or wall outlet controlled by a switch, this is a standard part of any home inspection to check that this is present.  As home inspectors we follow the American Society of Home Inspectors (ASHI) Standard of Practice and the Electrical System inspection requirements.  Explore the other electrical concern articles we have on our website.

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