A. Longevity of a fence depends on the type of material selected, proper installation, care and maintenance, and in some cases environmental factors including sun, water, and wind exposure. Assuming normal environmental conditions and sufficient care & maintenance, typical longevity in a standard six foot cedar fence with 4x4 cedar post is 20 to 25 years. You can increase the longevity of your fence dramatically by using steel post designed for wood fences.