There are ways to hang a gate—and ways not to hang a gate. A properly hung gate will swing correctly and won't sag.
For this project we worked with Gene and Alicia Hamman of Quality Farm Fencing. The husband-and-wife team has been building fences for a long time—Gene for 18 years. Here, they hung two 10-foot gates to create a 20-foot opening. Two steps are important to keep this gate from sagging.
First, put in sturdy hinge posts. For this project, Gene used 7-foot, creosote-treated round posts. He sunk them 2 feet, 6 inches in the ground. For larger spans—16- or 20-foot gates—he uses 8-foot posts buried 3 feet. Take your local conditions into account. Cold climates require deeper postholes to avoid damage from the frost.
The second step is to use the correct hinges. The gates here come complete with screw-in hinges. Over time, however, this type of hinge tends to pull loose from the post.
Instead, Gene uses 3/4-inch, all-thread hinge bolts that extend all the way through the post. That way the nut can be adjusted as the position of the gate changes with time.
See next page for step-by-step instructions and photos of this project.
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1. Line the gate up along the vertical center line of the hinge post. Also use this step to locate the position of the bottom hinge. If the ground isn't level, make sure the far end of the gate is high enough off the ground to allow free movement.
2. Sink the first fencepost to the other side of the hinge post, opposite the gate. Locate a 4-inch-diameter brace post between those posts. Each end should be supported by a notch cut into the two posts. The notches don't need to be more than 3/4 inch deep.
3. Drill holes through the hinge post, as well as the first fencepost, and into the beginning of both ends of the brace post. Drive 12-inch galvanized spikes into those two holes. To give strong support to the gate and the fencing, make sure to add lengths of strainer wire to the first pair of posts on either side of the gates. These are wires—pulled tight by a strainer—mounted diagonally between the hinge post and the first fencepost. The strainer wire balances the downward pressure exerted by the gate and the outward, pulling pressure of the fenceline.
4. Stretch a line across the length of location for the gate. Along that line, sink two hinge posts—one for each gate. The 7-foot posts are round and treated all the way through with creosote. Here, they are buried 21/2 feet in the ground. Add two bags of dry concrete. You don't have to add water, unless the ground is extremely dry. For longer gates use 8-foot posts.
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5. At the location of the bottom hinge, drill holes through the posts to accept the all-thread hinge bolts. For this project we used 3/4-inch bolts. Screw-in hinges were included with the gate, but they can pull out over time. These bolts—$11 each at Tractor Supply Company—can be adjusted over time as the position of the gate changes.
6. To locate the position of the top hinge, measure the distance from the bottom side of the bottom hinge to the top of the top hinge. Remember, the top hinge bolt is pointing down. This prevents cattle or horses from lifting the gate off its hinges and also slows thieves from removing the gate. Slide the hinge bolts through each post. Loosen the top hinge on the gate and slide it down. Set the gate onto the bottom hinge bolt. Position the top gate hinge immediately below the top hinge bolt. Slide the gate hinge back into place and tighten.
7. Align the two gates. Make sure they close with only a small space separating each gate. Also, make sure the gates align horizontally. Make these adjustments by turning the hinge bolts in or out.
Here are detailed photographs of the two types of hinge bolts considered for this project. We used the all-thread bolt (above left) that can be adjusted over time. The screw-in bolt (above right) will not hold the gate level for long, but the larger bolt we used can be adjusted.