Question 1

How deep should a fence post hole be?

Accepted Answer

The general rule is 1/3 of the total post length should be buried. For a 6-foot fence using 8-foot posts, dig 24-30 inches deep. In frost-prone areas, holes should extend below the frost line (typically 36-48 inches) to prevent heaving.

Question 2

How wide should a post hole be?

Accepted Answer

Post holes should be 3 times the width of the post. For a 4x4 post (3.5" actual), dig a 10-12 inch diameter hole. For a 6x6 post (5.5" actual), dig a 16-18 inch diameter hole. This provides adequate concrete around the post.

Question 3

How many bags of concrete per fence post?

Accepted Answer

A typical 4x4 fence post in a 10-inch diameter, 36-inch deep hole needs about 1 bag of 80-lb concrete (0.6 ft³) or 1-2 bags of 60-lb concrete (0.45 ft³ each). Deeper or wider holes require more.

Question 4

Can I use quick-setting concrete for post holes?

Accepted Answer

Yes, quick-setting concrete (like Quikrete Fast-Setting) is ideal for fence posts. Pour the dry mix into the hole around the post and add water. It sets in 20-40 minutes, so you can continue building the same day. Regular concrete sets in 24-48 hours.

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