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How to Install Fence Posts on a Concrete Sidewalk

By Keith Allen

Fence posts are commonly set in holes in the ground. That's not possible when then post must be placed where a concrete sidewalk or other slab exists. Installation difficulty varies depending on the type of fence post. Metal posts associated with a wrought-iron fence often have brackets at the base for attachment to a concrete or wood surface. A separate metal bracket is required for wood posts. Do-it-yourselfers with access to a hammer drill or power drill with a masonry bit will find the project within their abilities.

Mark the location of the proposed post with chalk. Measure the exact location of the post with a tape measure because you will only have one chance to set it in the right spot. Mark the locations of the drill holes for a wrought-iron post base or the locations of the holes in the post base for a wood post.

Drill holes in the concrete, using a hammer drill or a power drill with masonry bit. Use a bit approximately three times the diameter of the bolts that will hold the post to the concrete sidewalk. For example, a 1/4-inch bolt will require a hole in the cement 3/4 inch in diameter. Drill each hole about 3 inches deep.

Insert the masonry inserts, sometimes call lag shields, into the hole. These inserts are sold with the masonry lag bolts or screws.

Place the wrought-iron post base or the wood post base over the holes with the inserts in place. Align the holes of the bases with the inserts.

Insert the screw or lag bolt, with a lock washer in place, into the insert. Use a screwdriver or wrench to tighten the screw of lag bolt into the insert. The insertion of the screw or bolt causes the masonry insert to expand and create a tight grip against the concrete.

Install the wood fence post in the post base. This commonly involves wood screws or lag bolts running through portions of the base that run up the side of the post.


Things You Will Need

  • Chalk
  • Tape measure
  • Hammer drill or power drill with masonry bit
  • Post base
  • Masonry bolts or screws with masonry inserts
  • Screwdriver or wrench


  • A dab of concrete adhesive on the inserts before it is pushed into the hole improves the hold of the bolt or screw.


  • The placement of the post must be correct before the holes are drilled. If you are off a little bit, a second set of holes near the first will weaken the concrete.

About the Author


Keith Allen, a 1979 graduate of Valley City State College, has worked at a variety of jobs including computer operator, medical clinic manager, radio talk show host and potato sorter. For over five years he has worked as a newspaper reporter and historic researcher. His works have appeared in regional newspapers in North Dakota and in "North Dakota Horizons" and "Cowboys and Indians" magazines.