Solar panels will last many years, (over 25). Because of this, we want the roof to be in decent condition, as it does not make sense to remove and reinstall the panels after only a few years. However, after the panels are in place, they will greatly reduce the wear on the roof by blocking ultraviolet rays, keeping most snow and ice off the roof, and keeping anything from hitting the roof. Most installations do not require a new roof prior to PV installation.