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How Much Concrete per Fence Post Is Best to Use – What To Know

Fence posts and concrete bases

When putting up a fence, it’s recommended that you use concrete for the fence posts, as it will give your fence a more solid foundation and make it last longer. But how much concrete per fence post is best to use?

That’s what we’ll be answering in this article! Depending on the size and weight of your fence posts, the amount of concrete you need to use may vary. We’ll discuss this below, so keep reading to learn more.

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How to Use Concrete

When it comes to concrete, it’s always better to err on the side of using too much rather than too little. This is because if there are any gaps in the concrete around the fence post, water can seep in and cause the post to rot.

This will eventually cause the fence to become unstable and could even lead to it collapsing. That said, it’s still important to know precisely how much concrete is needed for optimal support and stability.

Concrete pouring during commercial concreting floors of building
Photo Credit: Bannafarsai_Stock, Shutterstock

How Much Concrete Should You Use?

A good rule of thumb is to use about 1/3 of the post’s above-ground height in concrete. So if your fence posts are 6 feet tall, you would need to use enough concrete to fill in 2 feet of the post. Of course, the post itself will take up some of the hole’s depth. But the remainder needs to be filled in completely with concrete.

On average, this comes out to anything from one to four bags of concrete. You may need to adjust this amount depending on the weight and size of your fence posts.

In addition, you need to consider the size of the hole. As a rule, each hole should be three times the size of your fence post. So if you’re using 4×4 fence posts, the diameter of the hole should measure 12 inches.

From there, you can determine how many bags of concrete to use. Let’s assume your fence is 6 feet tall. You know you have to fill a hole that’s 12 inches wide, but you also have to take into account that 1/3 of the post’s height will be covered in concrete, as well.

It takes approximately five bags of 80-pound concrete to fill such a hole. After factoring in the space the fence post takes up in the hole, it comes out to about four bags of concrete.

How Many 50-Pound Bags of Concrete Do I Need for a Fence Post?

It takes approximately eight 50-pound bags of concrete to fill a hole for a fence post using the dimensions discussed above. That leaves you with to accommodate both the hole’s diameter and the space the post takes up.

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Final Thoughts

Concrete is a very versatile material, and there are many different ways to use it for your fence posts. The best way to determine how much concrete per fence post you need is to take into account the hole’s diameter and the size of the post. From there, you can adjust the number of concrete bags needed to get the job done.

Featured Photo Credit: Kaninw, Shutterstock


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