Exterior wall vent covers help remove the heat and moisture that can build up in a home’s ducts. Exterior wall vents are also needed to relieve the pressure that might have been building in the ventilation threatening to damage the system if the pressure is not released. Without exterior wall vent covers to protect the ventilation system that has been installed the ventilation system as well as the home can suffer damage. Exterior wall vent covers are placed over the vent in order to prevent certain elements from creating havoc on the home. Exterior wall vents have the ability to dispel moisture, heat and pressure but also act as a barrier against weather elements such as rain, snow and hail.