Setting up Wi-Fi in a metal garage

Having Wi-Fi woes in a detached garage or shed? A powerline network kit can get you up and running.


Aerial view of Ghost Creek golf course
This small adapter module provides wireless and hard-wired internet connectivity in the garage, overcoming the difficulties of the metal building blocking signals from cellphone towers and our internet router installed about 75 feet away in the house. Photos by Scott R. Nesbitt

I solved the problem of getting on the internet when in my metal garage. This may help others defeat connection problems.

Installation of a “powerline” kit gave the detached garage 30 megabits per second of internet bandwidth. My shop computer streams video without buffering. My cellphone has lots of bars. That 30 Mbps, measured using, is a lot less than the 200 Mbps I get from the fiber-optic line that serves my house. But I’m happy. Until May 2023, the Federal Communications Commission considered 25 Mbps to be high-speed broadband.

The $75 kit installed in five minutes. A small sending adapter module is plugged into the 110-volt wall outlet that feeds our modem. An Ethernet cable runs from the modem to the module. The sending module takes the digital internet pulses and inserts them into the house wiring in the form of a radio signal that travels through the wires alongside the house power — rather like an antenna wire.

Aerial view of Ghost Creek golf course
The sending module plugs into a wall outlet and gets internet connection from the white cable connected at the bottom. The module drops the internet signal into the house wiring, which carries it to the garage.

In the garage, a receiving module is plugged into a 110-volt outlet. This module pulls the radio signal out of the wiring and broadcasts a Wi-Fi signal that’s available for the phone and computer. The module also has a port for connection of a hard-wire Ethernet cable. The only setup was using my laptop to type in a security password.

This digital magic works if a single electric meter covers all the wires in the system. My setup is typical. Two large 110-volt wires come from the power company and feed the meter panel outside the house. Call one line red, the other black. From the meter, the power goes to a 200-amp, 220-volt main circuit breaker, which feeds a circuit breaker panel inside the house. The main breaker also feeds a 60-amp, 220-volt breaker in the outside panel; this feeds a 150-foot underground cable that feeds a disconnect box on the garage exterior that feeds an interior circuit breaker panel that feeds outlets in the garage.

The powerline system works best when both modules are on the same circuit, red or black. The signal drops but usually gets through if the signal must cross red-to-black. You can find which garage wall outlet mates with the sending unit’s outlet with a circuit breaker finder tool. These cost under $50 and are a worthy addition to your maintenance toolkit.

Aerial view of Ghost Creek golf course
The cheapest circuit locator tool from was able to identify the circuit holding the receiving module and traced the circuit at the service panel line source 150 feet away.

The more wires and circuit breakers, the weaker the final signal. Strength is also affected by the age and condition of wires and breakers and details of the meter system. Signal can be blocked or weakened by surge protectors, arc-fault or ground-fault circuit protectors, and power strips and extension cords. Electrical “noise” from motors, USB chargers and other appliances can garble the signal, causing delays in uploads and downloads.

Altogether, the setup was plug and play and is keeping me from tracking mud into the house when I need to get on the internet … and I no longer miss phone calls.

Scott R. Nesbitt is a freelance writer and former GCSAA staff member. He lives in Cleveland, Ga.