Key takeaways
- About a third of the post should be underground
- Where the ground freezes, go below the frost line
- Gravel under the post helps drainage
- The Footing Planner gives a quick estimate
The part of a fence you never see decides how long it stays straight.
The one-third rule
A common rule of thumb is about a third of the post below ground, more for tall fences and soft soil.
Frost
Where the ground freezes, posts are often set below the frost line so winter does not push them up.
Gravel and concrete
A layer of gravel helps water drain, and concrete locks the post in. The Footing Planner on this site gives a quick estimate.
Related services
Questions about your own property? Call or text 800-224-9245, or use the estimate form below.