Planning and building a fence

A fence is mostly a set of repeated parts: posts, rails and boards. That makes it easy to estimate, and it makes mistakes easy to repeat. If the posts are wrong, every section after them is wrong too. The posts are also the part that fails first, so they deserve most of your care.

This planner starts with the rules and the layout, and works through the posts, the concrete, the framing and the boards.

Step 1: Check the line and the rules

Know exactly where your boundary is. A survey or the markers on your plat are better than the old fence. Many places limit the height of a fence (often 6 feet at the back, less at the front), require it to be set back from the property line or the sidewalk, and need a permit. Some neighborhoods have their own rules. Call 811 before digging.

Step 2: Lay out the line and the posts

Run a string line and mark each post position. The usual spacing is 6 to 8 feet on center, set by the length of your rails and boards. Corners, ends and gates need posts of their own, and a gate post carries the extra load so it needs more depth and concrete.

Step 3: Dig, set and plumb the posts

As a rule of thumb, bury a third of the post, or at least 2 feet for a 6 foot fence, and go below the frost line in cold areas. A bed of gravel under the post helps drainage. Set the posts plumb with a level on two faces, and brace them while the concrete cures.

Step 4: Frame it and hang the boards

Rails run between the posts, usually two for a 4 foot fence and three for 6 feet. Hang the pickets or panels from a level line, keeping the bottom clear of the ground by an inch or two so the wood does not wick moisture. Use galvanized or stainless fasteners, especially with cedar and treated wood.

Step 5: Add gates and finish

A gate needs a heavy post, good hinges and a latch, and it sags if it is not braced diagonally. Stain or seal the fence on a dry day, once the lumber has dried if it is new treated wood.

Before you start

• A survey or markers that show the boundary, and the local rules on height and setback.
• A permit if required, and a word with the neighbors.
• Call 811 before you dig the post holes.
• Posts, rails and boards stored flat and dry.
• The frost depth, which decides how deep the posts go.

Mistakes that cost people money

• Posts set too shallow, or with no gravel or concrete, so the fence leans within a few years.
• Setting posts first and finding the rails or panels do not fit the spacing.
• Putting the fence on or over the line without a survey.
• Letting the pickets touch the ground, which rots them.
• Using bright nails or plain screws, which stain and corrode.

Frequently asked questions