A post base is device used to help hold a post in place. It can be used to hold a post used for building structures, such as pole barns.
A typical post base looks like a large bracket that forms two 90° angles, while one end remains opened. The post that is being installed is inserted in this open area so it rests flat against the bottom of the base. The other side of the device generally has two protrusions, which are intended to be inserted in cement located at the bottom of the hole into which the post is to be inserted.
In order to use a post base, it must be attached to the bottom of the post with screws. A hole for the post must be dug, and cement is poured in. The post, complete with post base, is placed inside the hole, with the protrusions of the device inside the wet cement. It should usually be embedded about 1 inch (2.54 centimeters) from the base plate. This allows the majority of the wood portion of the post to stay out of the cement while still being held in place.
Since post bases remain in the ground, they are usually made of galvanized steel in order to prevent decay. Even though they are made with steel, they are not capable of providing enough resistance to keep the post from rotating if too much pressure is placed on it. For this reason, a post base should not be used for posts that will not be supported at the top, such as fence posts.
Using a post base to install posts rather than embedding them directly into concrete helps the posts last longer in the ground. In fact, a post embedded in concrete in this way can usually last for around 50 years.
