Fence Post Footing Depth

230mm wide 9 x 600mm depth.

Fence post footing depth.

For example if you are erecting a 6 foot high fence using 4 inch fence posts the posts need to be 6 feet above the ground. Keep the height of your fence in mind when digging your post holes. To prevent a post from decaying too quickly as well as to. For example a 6 foot tall fence will need at least 2 feet of post in the ground.

Dig post hole so diameter of the hole is 3 times the width of the post i e the hole for a 4 wood post should be about 12 inches wide. This rule of thumb. Instead you re depriving jack frost of a lip he can use to get a tighter grip on the concrete footing. As a general rule of thumb you ll need to place at least 1 3 the height of the post in the ground.

Fence posts anchored in concrete footings last for years as long as they re installed properly. For the width you need to make the hole three times the width of the post you intend to use. The depth of your fence post footings will vary according to fence height wind loading and soil type as well as other factors. For example if you have a 3 inch wide post that you need to sit over 1 83m 6ft in height above the ground we recommend the hole size should be.

Consider the frost. You need to dig a 12 inch wide hole for a 4 foot wood post. For example an 1800mm fence in wind zone a will require footings of a minimum of 600mm deep by 200mm wide whereas the footing dimensions for the same fence in wind zone d will need to be at least 700 1100mm deep. Even though it seems this would result in less stability this is not the case.

Building codes and ordinances in your area may stipulate a legal depth and diameter for fence post holes. Gates require a hole with a depth of 36 to 40 inches in the ground and with a diameter of at least 12 inches. As the post is 4 inches wide 3 multiplied by 4 is 12 so the hole needs to be 12 inches square. How to install fence posts in footing.

Here are a four tips to help you find the correct fence post hole depth. Don t make postholes too small. If you re still intent on setting fence posts yourself rather than having a professional do it the key is in filling the hole only halfway up with concrete. 6 divided by 3 is 2 therefore the depth of the hole required is 2 feet.

Set the post in the hole and brace it plumb or put a helper on the job and in line and level with the posts. If your post is 6 feet tall you will dig down at least 2 feet. If not conventional rules of thumb offer a reliable guide.