The hardest part of building your own fence is digging the holes; after that, the structure takes shape quickly. Besides a rented posthole digger, you'll need only a circular saw and ordinary carpentry tools.
Designs vary widely, but just about all fences consist of the same basic elements: A series of posts sunk into the ground and connected by rails on the top, bottom, and usually in the middle as well; and fencing boards or panels that are nailed to the rails to give the fence its character. Privacy fences usually require 4x4 posts. Rail and fencing lumber can be almost any size. Lumber yards sell prefab sections of fence in many styles, but custom design and construction usually yield a better-looking fence.
Before proceeding, check community building and zoning codes. Many specify maximum fence height, distances you can build from property lines and the street, and even the materials you can and can't use. Once you've chosen a design and established a location, stake out and measure the site. Plot post spacing for the most efficient use of lumber. Six- or seven-foot spans usually work well; never set privacy-fence posts more than 8 feet apart. If you're building your fence on a slope, plan to step the fence down the hill, setting each section lower than the one preceding it. Only if the slope is slight—and the fence design won't suffer—should you follow the contour.
Editor's Tip: Always call your local utility companies before you start a project that requires digging in your yard. Have all lines clearly marked before you finalize your plan to make sure your project doesn't interfere with uderground lines.
When you order lumber, specify construction-heart redwood or cedar or ground-contact, pressure-treated wood for all posts and bottom rails; upper rails and fencing can be less expensive grades of rot-resistant lumber. To minimize rust, buy hot-dip galvanized nails and fittings. If you want to paint or stain your fence, apply the finish to posts, rails, and fencing before you nail up the fencing. Besides saving time, you'll get better coverage.
Lay out the site, dig holes, and set posts, starting with the end posts. Check each post for plumb by holding a level to two adjacent faces; nail braces to hold posts upright. Check, too, that posts are aligned by tying string from end post to end post.
As you shovel concrete into the holes, have a helper tamp the concrete to remove bubbles. Round off the concrete so water will drain away from the posts. After the concrete cures, cut posts to a uniform height, if necessary. Shape tops of posts so they'll shed water.
Attach the rails to the posts. We installed our rails face up and added extra support with a right angle piece of wood, but you can also use galvanized rail clips to speed up this process. A line level and combination square assure that each rail is level and square with the posts.
Measure carefully and use a square to mark locations on the rails for each fencing board. Wood scraps squeezed between boards maintain uniform spacing. Have a helper align boards—in this case flush with the bottom—while you secure them to the rails.