how to install fence post

How to Set Fence Posts That Won't Rot

Keep moisture and insects from destroying your cedar fence posts.

Time

A full day

Complexity

Intermediate

Cost

$51–100

Introduction

Cedar has a reputation for durability, but unless a few guidelines are followed, cedar posts can fail in as few as five years. Three factors contribute to this early failure: poor drainage, low-quality wood and poor protection against insect damage. Here's how to install new cedar fence posts and avoid the problems that made your old posts rot.

Tools Required

Materials Required

Acrylic caulk
Aggregate
Cement
Wood preservative

Project step-by-step (5)

Step 1

Pick the Right Posts

Don't use posts that contain sapwood. Instead, use heartwood, because it's denser and more insect-resistant.

Step 2

Treat the Post With Preservatives

Soak the bottom of the posts in a wood preservative containing copper napthanate, such as Cuprinol.
- Note: Available at some paint stores and home centers, this wood treatment is specifically designed for in-ground applications.

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Step 3

Insert Aggregate

Place about 6 inches of aggregate in the bottom of the posthole to allow for drainage.
- Pro Tip: The bottom of the post should extend a few inches into the aggregate as shown.

Step 4

Pour in Concrete

Concrete should be 2-3 inches above the soil level.
Trowel the top smooth and slope it so that water runs away from the post.

Step 5

Caulk Around the Fence Post Base

Apply high-quality exterior acrylic latex caulk, or silicone specifically designed to adhere to concrete, at the base of the post.
- Note: This will seal the gap between the concrete and post that's caused by freeze/thaw cycles.