Fence Post Depth Code

Common construction requirements include post size spacing and depth.

Fence post depth code.

The maximum frost line depth is 100 inches as seen near the tip of minnesota north dakota and alaska all the way to zero inches in florida southern arizona and southern california. Others leave that up to the builder. For example a 6 foot tall fence will need at least 2 feet of post in the ground. The depth of your post hole plays a key role in the strength of your posts.

For example a 6 foot tall wood fence may need 4 x 4 or larger posts spaced no more than 6 feet apart and buried in the ground at least 2 feet deep. Keep the height of your fence in mind when digging your post holes. Check your frost line by zip code or address using this map from the national weather service. Gates require a hole with a depth of 36 to 40 inches in the ground and with a diameter of at least 12 inches.

Here are a four tips to help you find the correct fence post hole depth. For the width you need to make the hole three times the width of the post you intend to use. Building codes and ordinances in your area may stipulate a legal depth and diameter for fence post holes. That is why there is a specified depth for building footings.

That also means that you d need to use an 8 foot post. If your post is 6 feet tall you will dig down at least 2 feet. It s a lot harder to push over a post that s buried deeply so always keep that in mind. For a structure it is important since any cracks caused by heaving will destroy the servicablity and appearance of the structure.

Some cities say posts must be set in concrete. Frost line by zip code. The depth of the post hole needs to be 1 3 to 1 2 the height of your fence. If the map isn t accurate enough for you.

The code frost depth is meaningless for a fence. For a fence a little heaving is not easy to notice and does not destroy the servicability of the fence. As a general rule of thumb you ll need to place at least 1 3 the height of the post in the ground. For example if you are building a fence that s 6 feet tall you will need a hole that is at least 2 feet deep.