All structures should have a vent or two. Ventilation of any building allows air movement throughout which helps to keep moisture under control. It also aids in keeping heat from collecting under the roof which could impact the life of your shingles.
The vents we use are 8” by 8” and made of white plastic. The design of the vent is to prevent rain water from entering the shed or garage. Vents are always installed in the peak of the roof in order to allow hot air to escape. They are installed by cutting a hole in the wall to fit the vent in and secured using screws. The entire outer edge is then sealed with moisture resistant caulking.