Fence Posts Need Dry Anchor to Prevent Rot

Coming from a family of builders, we weren’t strangers to hammers and nails when we were children.

While most of our playmates were using a wooden hammer to drive wooden pegs into a wooden bench, we were using the real things.

We graduated from wooden pegs to full-fledged nails when our folks decided we didn’t pose a threat to anyone or anything.

With vivid imaginations and plenty of scrap wood and nails, we were never at a loss for new projects.

Toys, boxes, stools and even a fruit stand were among our favorites.

As we grew older, our ability to drive a nail became a useful skill around our house. Soon, we found ourselves helping our dad with an array of repair projects.

One of our first solo building projects was a fence. The work included layout, digging, pouring concrete, framing and the installation of fence boards.

Though our fence-building experience taught us many lessons, the one that stands out is the importance of properly installed fence posts.

We learned that posts are to a fence what a foundation is to a house. Without solid fence posts, the fence would not be stable--it could lean after a few years or blow over in a brisk wind.

Early on, fence posts were simply stuck into a hole in the ground or were surrounded by stones for support. Once concrete came along, there was plenty of support, but rot became a problem. Fences weren’t leaning, but posts were rotting and breaking off at the top of the concrete.

After the post is placed in the hole and surrounded by concrete, it may lift slightly, which creates a well at the base of the post. Consequently, the base of the post sits in a puddle of water, which results in rot. This condition can occur when the top of the concrete is not “crowned” to drain away from the post.

When placing posts in the ground for a fence, mailbox, windbreak, trash enclosure or other outdoor project, always put about 6 inches of crushed rock or gravel at the base of the hole to ensure good drainage and prevent rot. Once the bottom of the post is placed against the gravel, leave it there.

Don’t pull up on the post after concrete has been poured into the hole or you’ll end up defeating the purpose of the gravel.

Also, concrete should be poured level with the grade and have a slight crown so that water will drain away from the post and prevent rot at this vulnerable location.

Although we still believe using concrete is one of the best methods of setting a post, there are alternatives to the traditional premixed concrete method. The first involves concrete; the other does not.

Instead of mixing concrete in a wheelbarrow and shoveling it into the posthole, partially fill the hole with water and pour in a dry concrete mix. This speeds up the process and cuts down on the mess. What’s more, these materials are designed to dry more rapidly.

The other alternative involves the use of a large metal stake that is driven into the ground. This eliminates the need for digging and concrete. Stakes come in 24-and 30-inch lengths. The longer model is for larger, heavy-duty projects. The post is bolted into a collar at the top of the stake. Be sure to check with your local building department to determine that this type of system can be used for your particular project.

Whichever means of setting a post you decide to use, be certain that there are no pipes, gas lines, wires or other utilities in its path. When in doubt, check with your local utility or private service (whichever applies) to locate underground lines.

For more home improvement tips and information, visit the Careys’ Web site at https://www.onthehouse.com.