How to build a fence
How to Build a Fence
Building a fence is a very labor intensive process that requires a few specialty tools and some general construction knowledge. Below is a brief description of the process that I follow when constructing new fences. Before we dive in, you should always have proper safety equipment and understand how to comfortably operate the machinery to prevent any injury or property damage.
The first step is to look into covenants to see if there are any restrictions as to the type of fence you can build, height limitations and setbacks required. Select the appropriate fence based on your needs and covenant requirements. Have utilities located and marked. This usually takes about 3-4 days prior notice.
Once you have the utilities marked, fence type selected and approved you can begin to lay out the area for the new fence. If there is tall grass where you plan to install the fence, it is best to mow or weed eat approximately a 3 foot wide path down the line so you can run a string line. Another option is to tightly stretch a strand of wire so that you do not have to mow the line. The key to the string line is to place it about 4”-6” from the ground and make sure it is tight. The reason for the string at the bottom is to make certain the bottoms of the posts are in a straight line. After all of the posts are driven into the ground, you can move your string up to the tops of the posts and use a metal bar and level to align the tops of the posts.
Once the string line is up, you can start to lay out the posts. Typical post spacing is 8 feet on center for wood rail and/or board fences and 12-14 feet on center for field fence or barbed/smooth wire. Make sure that you clearly mark where all posts are to be placed and don’t forget to mark out your gates.
Gates typically start at 4 foot in length and increase by 2 foot lengths up to 16 feet long. The common exception to this is the standard 3 foot gate. If you space your posts for the size of the gate your gate should be able to swing both ways. For example a 10‘ gate is actually 9’ 6” long so if you space the posts at 10’inside length then you will have approximately 3” space on each side of the gate for a latch and hinges.
To install the posts I recommend using a post driver, whether it is a vibratory driver on a skidsteer or a hammer pounder on a tractor. This, in my opinion is better than digging them by hand or using an auger. You can rent post drivers and machines by the ½ day, whole day or weekend and many contractors will provide you with a quote if you don’t feel comfortable putting the posts in yourself. If you plan to build a wire fence without any boards or rails, you will need to build braces at the beginning and end of straight runs, on both sides of gates and every corner. Brace posts should be spaced at approximately 8 feet.
In this example I will discuss how to build the standard cross brace. After the posts are installed at 8 feet apart, you will need to mark the inside of the two posts at the height of the wire you will be installing. When installing 47” tall field fence, what I typically do to mark the height of the H brace is to roll the wire out a few posts past the brace point, stand it vertically and mark the brace posts so that the brace will flow with the ground and how the wire sits. Once you have the tops of the post marked you can measure the diameter of the horizontal brace rail and mark the posts for the bottom of the brace notch. With the two posts marked you can use a chainsaw to cut several cuts typically the depth of the chain and about 1/2” or so apart between the two lines on each post. Take the claw end of a hammer and break out all of the small pieces you just cut. Once removed take your chainsaw and smooth out the imperfections to create a solid rest for the brace to sit. Place one end of the horizontal brace into the rest and the other alongside the other post at the height of the notch and mark the brace for the correct length and cut with a chainsaw. Now place the horizontal brace into both rests and check the fit. If there is a large gap, carefully straighten with the chainsaw and then secure the horizontal brace with nails or fencing screws.
Once the horizontal brace is in you will need to place staples at approximately 4” from the ground on the back side of both posts (outside of the brace and in line with the fence). You will also need to place staples at the top of the horizontal brace as well. Pound these staples in approximately half way as you will be pulling wire through these. Now run smooth wire from the bottom staple of one post to the top staple of the other post and wrap the wire around the post and tie it off on the outside of the brace post. To tie it off, twist the wires together and cut the slack. Repeat the same process for the other side of the cross brace only this time before you tie it off check the slack in both wires to make sure they have the same tension. Tie this one off and get a piece of split rail, 2x4 or piece of rebar that is about 32” long and place it in the center of the brace between the wires where they all cross. Begin to twist the wires paying attention to the direction of the twist because you will want the “twist” bar to rest against the horizontal brace and the wire. Make sure that you don’t twist the wire backward and end up having the “twist” bar on the opposite side of the wire. Keep twisting until the all of the wires are tight creating a solid brace to tie your wire for an effectively stretch. Nail the twist bar to hold it in place while stretching the field fence and pound in your four staples. Repeat this process for every corner, every gate and at the end of your fence.
Once all of the braces are installed you are ready to stretch the wire. One common mistake is that people only staple the wire to the posts. It will make a much stronger fence that will last longer if you cut and remove 3-4 vertical wires from the beginning of the roll leaving only the horizontal wires attached. Stand the wire up next to the post making sure that the wire is straight with the post. You can do this by lining up the first vertical wire to the center of the post and staple every horizontal wire at the vertical point. Now take every horizontal wire and wrap it around the post and tie it back to itself with 3-4 wraps. Repeat this through all of the horizontal wires. Roll out the remaining wire about 10 feet past the last brace in the line and attached the stretcher to the wire. The stretcher is just two 2x4s that have been drilled to accept 4-5 bolts. Place one board on the outside of the wire, one on the inside and sandwich it together with the bolts. Attach a chain around the top of the stretcher and again at the bottom of the stretcher creating a loop. Place a come-along at the center of the loop and use a chain at the other end of the come-along and attach that to a tractor, atv or truck. Use the truck to pull the wire tight watching the first brace to make sure there is no movement. In very wet areas you can sometimes pull the braces out of the ground if you are not careful. Once the wire is tight you can use the come-along to finish it if necessary. Now go through and staple the bottom two horizontal wires and every other one after that on all of the fence posts. If you stretched past a gate opening you can staple every horizontal wire and go back and cut the vertical wires from the gate opening and tie the horizontal wires back to themselves like the first brace. Repeat for the end of the line as well.
To hang the gate you will need to use a straight edge and a level or a long level to mark the center of the gate post. This will give you a line to make sure that your gate hangs straight up and down and not at an angle one way or the other. From there place the gate in the opening and align spacers, typically 2x4 or 2x6s under the gate to get the gate as close to level as possible. Now put the bottom hinge bolt into the bracket on the gate and swing the hinge bolt toward the post. Make sure the bracket is centered between the rails on the gate so that you will have room to raise or lower the gate as necessary to ensure it will open if the ground slopes and so animals cannot crawl under. Mark the top and bottom of the bolt on the vertical line on the post to provide you with the mark to drill the hole for the bottom hinge bolt. Now repeat the process for the top bolt only place the top bolt upside down into the bracket on the gate so that animals and people can’t lift the gate off of the hinges. Mark this one and remove the gate so you can drill the holes. Drill the holes using a bit that is slightly smaller than the hinge bolt. This will make it easier to install the bolt, but also leave enough material for the bolt to hold onto the post. Twist the bolts into the post leaving approximately 3” of the bolt out of the post. Hang your gate and verify the level. Adjust the hinge bolts as necessary to get the gate level and aligned with the fence.
If you are installing rails on the fence, make sure to space the posts correctly. You can also disregard the bracing as your rails will work as the brace. When stretching the wire you can use a temporary brace that is screwed to the back side of the fence starting at the top of the first post and angling down to the bottom of the third post with screws in all three posts to hold the first post from pulling out while stretching the wire. Do the same thing at the end of the line and hang your rails. Once all of the rails are up you can remove the temporary braces. Finally you can stain or paint the posts and rails or let them naturally fade in color.