Building a Good Fence - Setting the Posts

Second Step - SETTING THE POSTS

The first post determines all other posts. Decide where you are going to start and dig a deep hole. You want to be between 2-3 feet down for your wood posts. These corner posts are going to take a lot of stress so it is important that they are very secure. They will determine the tightness of your fence and the overall durability through time.

Once you have the hole, set the post in the hole and mix at least two bags (80 pounds) of concrete. Fill the hole with concrete, rattling the post around to make sure that the concrete settles in. Using a short level, adjust the post until it is plumb. Don't forget to check it all the way around. Leave it to set overnight.

Once the first post is set, you can begin to measure for the other corner posts. Using a tape measure, measure from the center of the first post to where you want the second post. This will also determine the orientation of the pen so plan accordingly. Set the second post the same way you did the first.

The third corner post needs to be measured a little differently. You want to eventually have a square pen, so you need to make sure that the third post fits into the right orientation. Using the Pythagorean theorem, you can make sure to create a right triangle at the first post. It sounds fancy, but it's pretty simple. Pull a string line (a string that is tied from post to post) between the first two posts. Then measure out the length of string for the second side (third post) and tie it to the first post and to a t-post. Pull the string tight and estimate a square by looking at the first side of the pen. Stick the post in the ground (temporarily) and walk back to your first post. Now, here comes the math...measure out three feet on one side and make note. Measure out four feet on the other side and make note. Measure between the two points noted. This hypotenuse (the diagonal line) should be five feet. If it isn't, you need to adjust the second side in or out (in makes it shorter, out makes it longer) until it is. Once you have a triangle with a 3ft, 4ft, 5ft measurement, you know that your corner will be square. Replace the t-post with a wooden corner post. Set it the same way you did the other two.

The fourth post needs to be measured off of the second and third posts. Make sure that the sides are equal. If you want to double check the square of your pen, use the Pythagorean theorem again and measure the diagonal from the fourth post to the first. The hypotenuse (diagonal line) should be the sum squared of the two sides squared (a2 + b2=c2). Once you are sure of your measurement, set the fourth post the same way you did the last three.

Think about where you are going to want your gates. Whereever you decide to put them, you will want to have wooden posts on either side. We often use a corner so that we can maximize the uses for our wooden posts. Be aware that you want to decide on the size of the gate and create an opening exactly that size. Gates are labeled 4ft, 5ft, 6ft, but they measure about four inches shorter than their label to allow for hinges when installed. You do not need to add width to your opening (ask me how I know this?).

If you are building a large pen (over forty feet on each side), you are best off creating what's called an "H" corner. To do this, you use seven wooden posts per corner. Measure out six to eight feet from the corner post and set another post. Do this on both sides of the pen, making sure that it is in line with the far corner post (this is where a string line is very helpful). Once the two posts are set in the ground, create a top rail and bottom rail between the corner and the new posts. This makes the "H." If you want to make it even stronger, loop some fencing wire around the top of the two posts, cross them in the middle, and loop them around the other post - creating an X on each H. Take a stake (or a strong stick) and twist both wires around the stake at their junction until the wire is as tight as you can make it. Tuck the end of the stake behind the wire so that is will stay. But this costs money, and if you are like us, you would like to stretch your fencing dollars as much as possible. So, here's what we often do...

T-Post used as a corner brace.

In line with your side, pound a t-post into the ground diagonally, creating a triangle between the t-post, the wooden post, and the ground. Pound the tip of the t-post into the side of the wooden post. This allows the t-post to take much of the strain as the fencing is stretched around the pen.

Next, you need to put your side posts into the ground. At our ranch, we are best off drilling post holes with an impact drill. Some places you can just use a post pounder. However you get your posts in the ground, you want to make sure of two things. First, you have the posts in line with the rest of the side of the fence (a string line helps to ensure this). Second, you want to decide how you are going to orient the post for the fencing. Are you more interested in keeping a strong animal in or keeping a strong predator out? If you think your fence will take more pressure from the inside, orient your t-posts so that the "buttons" are on the inside. If you think it will take more pressure from the outside, orient your t-posts so that the "buttons" are on the outside. Buttons on the inside, means that you will be running your fencing on the inside of the posts and vise versa.