Outdoor Outlets: What Actually Makes One Weatherproof

Three parts have to be right, not one

People think of an outdoor outlet as "an outlet with a cover." It is really three decisions:

1. The enclosure and cover, which has to keep water out — including while something is plugged in.
2. The protection, which for an outdoor receptacle means GFCI.
3. The receptacle itself, which for outdoor use is a weather-resistant type.

Get one of the three wrong and the assembly fails at exactly the moment it matters.

"In-use" covers vs the old flip lid

The small hinged flap that snaps shut over the slots only works when nothing is plugged in. The moment you run a cord through it, it props open and the box is open to the weather.

An in-use cover — sometimes called a bubble cover — is a deeper hood that closes around the plug with the cord still in it. That is what an outdoor receptacle in a wet location needs if anything is going to stay plugged in: holiday lights, a pump, a fridge on a patio.

Damp location vs wet location

These are not interchangeable words.

• Damp — under a covered porch or a roof overhang, protected from direct rain but exposed to moisture in the air.
• Wet — an exterior wall with nothing over it, a patio, anywhere direct water can reach.

Equipment is listed for one or the other. A damp-rated cover on a wall that takes rain is a slow leak into a box full of connections.

Weather-resistant receptacles

Look for the "WR" marking on the face. These use corrosion-resistant components and materials that hold up to UV and temperature swings. In coastal and marine air especially, an ordinary indoor device outdoors will corrode at the terminals long before it fails visibly.

GFCI, and where it lives

Outdoor receptacles require GFCI protection. That can be a GFCI receptacle at the location, or a GFCI breaker in the panel protecting the whole circuit.

There is a practical argument for the breaker on outdoor circuits: the reset button stays indoors, dry, and reachable — instead of being on the outside wall in the rain, which is where it is most likely to have tripped.

The commercial version of the same problem

A storefront, a food operation or a community installation raises the stakes: the outlet will be used by people who did not install it, in weather, possibly every day, and possibly with an appliance that has to keep running. That is the case where the in-use cover, the weather-resistant device and the GFCI location all stop being preferences and start being the job.