How to Repair a Rotten Barn Post

Jonah Morrissey

Barn posts can start to rot near the base due to repeated exposure to water. It is important to repair a rotted barn post to maintain the structural integrity of the barn. You can repair a post without replacing it by using a post anchor and pouring a cement base for the post. Keep your barn in safe condition by making repairs to posts as soon as the problem appears. You can help prevent rot by treating the posts with a penetrating sealant or paint.

  1. Dig around the post with a shovel until you reach the base of the rotted post. Try to keep the dug-out perimeter around the post to a maximum width of 8 inches.

  2. Insert a column jack near the rotted post and raise the jack so that it will support the weight that the post is bearing.

  3. Saw off the rotted post approximately 3 inches below the splash board on the barn. Remove the rotted bottom portion of the post.

  4. Tamp the base of the hole where the post was removed with a tamper to make the surface flat and compacted by striking it in an up and down motion with the tamper.

  5. Pour cement mix into a cement mixer and add water until it has a batter-like consistency. Insert the round column form into the hole and pour the cement into the form to fill it.

  6. Raise the column jack enough to slide a post anchor under the bottom of the post where it was cut off. Fasten the post anchor to the post with the screws that were included with it, using a screw gun to drive them through the mounting holes in the anchor into the post. Lower the column jack so that the rod in the post anchor penetrates the cement and the base of the pole anchor rests on the surface of the cement.

  7. Allow the cement to dry for at least 12 hours. Fill in around the cement form with dirt and pack it down with your feet. Remove the column jack and allow the cement to cure for 30 days before working around the post to prevent bumping or disturbing it.