Common setups
Wall exhaust fan
Pushes hot air out high on a wall, with a vent lower down to let air in.
Ceiling / attic vent
Moves heat up and out.
Thermostat control
Runs only when the garage is hotter than a set point.
Fumes
Ventilation also helps clear out car exhaust and fumes from paint or solvents.
FAQ
Can a fan make my garage cooler than outside?
No. Ventilation can bring the garage closer to the outdoor temperature, but it can't go below it. In a Las Vegas July, the outdoor air is very hot too.
When does a fan help most?
Evenings and early mornings, when it's cooler outside, and in garages that trap heat well above the outdoor temperature.
Do fans need wiring?
Wall and ceiling exhaust fans usually do. Some use thermostats or timers. Ask the installer about options.