Erecting a fence on concrete
If you are erecting a fence on concrete, you can dig out holes and sink the posts in place, but it is much easier to use bolt-down brackets. These brackets are simply fixed to the concrete surface, and the fence posts are inserted and secured into the bracket socket. The technique shown here deals with a panel fence, but you can adjust the method according to your particular fence design. It is also worth you reading my guide – ‘Erecting a fence on soft ground’, as it provides some general information that relates to putting up a fence.
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1. Begin by marking the fence line. A long straight guideline is easily marked using a chalk line. Alternatively use a string line laid out and securely weighted down. |
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2. Position each bolt-down post bracket along the line at regular intervals to correspond with the width of your fence panels. It can be easiest to literally lay out the panels and posts to provide exact positioning. |
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3. Simply mark (with a pencil or chalk) through the fixing holes. Put the bracket to one side and drill to the correct depth using a power drill or SDS drill. Here I’m using expanding bolts to fix the posts in place. On the side of the bolts (or packaging) is normally a figure that relates to the drill bit size you should use. Be as accurate as possible when drilling the holes. |
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4. Re-position the bracket, before inserting and securing the bolts. Each bolt may first need tapping in place with a hammer before using a spanner to tighten in place. You can also do this by using the correct size of spanner bit with your cordless drill. |
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5. After inserting the post, tighten the socket bolts to secure the post in position. There may also be pre-drilled  holes on the bracket where you can insert screws as extra fixings. |
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As in the guide – ‘Erecting a fence on soft ground’, you should fit gravel boards along the bottom of the fence before fitting the panels in place using fence clips. If you need to dill further holes in the metal socket section of the bracket (in order to fix gravel boards) simply use HSS drill bits, which are designed for going through metal. Finally nail caps to the top of each post to protect the end grain from the weather, and create a neat finish. |
Fencing tips
- It is again worth looking at my soft ground guide for some general fence pointers.
- This bracket technique may also be used for decking projects where you need to raise a deck above some concrete.
- Because the posts are not sunk into the ground, repairs are made very easy as you can simply unscrew the brackets to replace broken or damaged posts.
