A fence is a great project for a homeowner to tackle themselves. But like so many other construction related projects, the important stuff that makes for a solid job is hidden or out of sight. Fence post holes for instance. Much of the stability and strength of your fence depends on the depth and preparation of your post hole. If a wood fence is in your future, you are likely installing 4×4 posts. A 10″ auger bit should be used, or alternatively a 10″ wide hole should be hand dug. That hole should reach about 42″ down for the typical four season climate. You may

need to go a little further in colder areas, but don’t skimp and use a shallower hole no matter how warm the climate is. Basically, 42″ will get you past the frost line. When frost arrives, it can’t heave the post up from the bottom because the concrete you’ll pour in to set the post extends past it. Even if frost is not an issue, you will still want to be around 42″ into the ground for good resistance against wind pressure and the weight of the fence.

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How Deep Should I Dig a Fence Post?