How to Build a Horizontal Fence
Building Basics, Choosing Wood, and DIY Instructions
Fences provide a look to a landscape as much as they do a function. Horizontal fences, running side-to-side, give fences a contemporary, modern look versus the traditional up-and-down vertical orientation. These sleek-looking fences are easy and straightforward for do-it-yourselfers to build. Ipe wood is a popular choice for a horizontal fence if you use hardwood; a less expensive option is cedar for a softwood alternative.
Once you get the posts properly set about six feet apart, it's just a matter of face-nailing the fence boards in even, level rows. You can butt them tightly together without spacing between the horizontal boards or allow for wood expansion and contraction that occurs with weathering by leaving a 3/8 to 1/4-inch space between boards.
Basics of Building a Horizontal Fence
A horizontal fence keeps many elements of a vertical fence, discards a few, and tweaks some measurements. Building a horizontal fence on a slope will require some extra measurements. On sloped property, you can "step" a horizontal fence or "rack" the fence by cutting the boards to follow the ground line contours.
Fence Posts and Rails
With a vertical fence, two fence posts are installed in concrete about eight feet apart. With a horizontal fence, the posts are moved two feet closer—about six feet apart to reduce the potential for sagging.
Rails for horizontal fencing add extra durability for the boards in-between the fence posts. Rails are hidden on horizontal fencing as they become incorporated into the overall look of the fence.
As an option, you can build independent frames within each post section to provide additional structure for the horizontal fence boards. Frames help eliminate sagging or drooping over time.
For vertical fences, 6-foot fence boards are nailed vertically to stringers, 16 boards per 8-foot section. For a horizontal fence, these fence boards are simply rotated to their sides, 90 degrees. You'll use only 12 instead of 16 because the span is shorter. As long as the fence posts are perfectly set, there is no need to cut them. The fence boards are face-nailed to the fence posts.
Nail heads do not need to be covered up. But if you do wish to cover them for a more polished look, you can add trim boards over the nails. Fence boards can act as trim boards.
Best Wood For Horizontal Fences
Because horizontal fence boards can sag over the long term, it helps to purchase high-quality hardwood fence boards. Ipe, tigerwood, and cumaru are a few of the hardwoods from Brazil or Indonesia that are often used for horizontal fences.
The cheapest way to build a horizontal fence is to consider a softwood for your building material. For a point of reference, hardwood ipe runs about $280 to $350 per 6-foot by 6-foot panel—fence boards only. Western red cedar, a softwood, costs about $30 to $60 to cover the same area.
Softwood fence boards are prone to sagging if they absorb water for an extended period. While some softwoods are left untreated for vertical fences, they must be sealed for horizontal fences. Regular sealing will help preserve softwood fence boards.
What You'll Need
Equipment / Tools
- Circular saw or hand saw
- Measuring tape
- Post hole digger
- 12 Fence boards, 6-foot by 6-inch by 1-inch nominal
- 2 Pressure-treated four-by-fours
- 1-3/4-inch (5d) galvanized nails
- 2 Fence post caps
- 4 bags Quick-set concrete
- 2 bags Gravel
How to Build a Horizontal Fence
Locate the Fence
Call 811 ahead of time to have any underground utilities located and marked with washable paint. The fence should be located on level ground. Mark the location of the fence post holes with stakes. They should be placed exactly 6-1/4 feet away from each other.
Clear the Fence Site
The ground around the fence should be clear, level, dry, and free of brush. Clear brush and debris with a rake. Level out the ground with a shovel.
Dig the Post Holes
With the post hole digger, dig two holes for the posts. Generally, the posts should be set about 20 inches deep or to the depth specified by your local code.
Add the Gravel and Concrete
Add about six inches of gravel to the bottom of each hole. Add the posts. Pour the dry concrete into the holes, packing the concrete around the posts. Pour water into the holes according to the concrete manufacturer's instructions. Let the concrete fully cure for about 48 hours.
Nail the First Fence Board
Start at the top of the fence. Align the first fence board with the tops of the four-by-fours (providing that the tops of the posts are level). Use the level to make sure that the first fence board is level. Nail the board into place with two nails on each side of the fence board.
Nail the Rest of the Boards
Working downward, maintain a space of 1/8-inch between the fence boards. Frequently check the level and adjust as needed. Cut the bottom board lengthwise if it will not fit. Instead of cutting, another option is to dig out enough soil to accommodate a full board.
Add Optional Trim
If you want to add trim, increase the purchase amount of fence boards from 12 to 14 and use two of the remaining fence boards as trim. Nail the trim vertically on the fence posts and cover both rows of nail heads.
Stain and Seal the Fence Boards
Apply stain, if desired, and seal the fence boards.
Is it cheaper to build vertical or horizontal fence?
Horizontal fences tend to be more expensive than vertical fences. They require a higher grade of lumber for the fence boards to reduce the threat of sagging.
How do I keep my horizontal fence from sagging?
Since horizontal fence posts are closer than vertical fences (six feet apart), this closer support keeps the fence from sagging. Also, get a higher quality wood and inspect the boards for defects before installing. To prevent the wood from warping or sagging, use a sealant to protect the wood after the fence is installed.
Does a horizontal fence need rails?
Fence rails span between posts and offer strength to the fence section. They are usually used on the top of the fence and the bottom of the fence. Since rails are horizontal features, they seamlessly fit into the design, matching the horizontal nature of the boards.