fence footing detail
How does fence post detail look?Answer:
A fence post detail look similar to detail 17 below minus the reinforcements. Most fence design use the post as reinforcements dropping it below the surface a good 18 inches or more.
The portion of the post below the ground level is embedded in concrete not only to prevent the post from corrosion but concrete also provide an anchor for the post. The protection concrete provides for the is temporary, its only a matter of time before corrosion gets to the wood or steel used as post. Due to its corrosion resistant ability, vinyl posts are great for fence posts.
Since fence posts are not subjected to vertical loads, it does not need a footing that we normally see on building. Instead fence posts require to be able to resist wind load. That's why fence posts are deeper than they are wider.
By inserting the post deeper in to the ground, it increases its resisting ability against wind, especially when embedded into concrete. The weight of the concrete add a lot of resisting force preventing the fence from toppling over during wind storm.
Another reason why reinforcements or rebars are not used at fence post is due to corrosion. Since the rebar will corrode as fast as the post, there is no need for the footings to remain strong at the end of the post life. At the end to the post life, the only fix is replace and therefore start with new footing. In other words there is very little benefit gained from adding reinforcements to fence post footings.