For years Metpost have been the biggest supplier of fence post holders, or post spikes, but now there is much more of a choice. There are several ways to fix, anchor or support fence posts and the most common is to concrete them in. Our project on fence posts shows how to do this. There are many occasions when concreting is not an option, for example when the neighbours patio is right on the boundary.
It might not even be a fence post you wish to secure. A Gazebo or Pergola needs posts and they are most often sited on existing patios or they can also be cited on decking.
Metal post holders and spikes solve the fence post problem in most ways. The spikes are simply driven into the ground with a sledge hammer but it is really advisable to put adriving block (shown in the image below) into the fence post spike first. This allows you to hit the spike as firmly as you like without bending the sides of the post holder.
The spiked fence post holders come in different sizes for different posts. They can be bought for posts which are 50 x 50mm, 75 x 75mm or 100 x 100mm. They come in two lengths, 600mm and 750mm. Do not use the shorter post holders for tall fences.
Bang the post holder into the ground making sure you check with a spirit level that it is going in vertically and not at an angle. If the post holder is leaning only ½ an inch (12mm) at ground level it means the post will be 12 inches out at the top. This is especially important if you are lining up a row of posts for a fence!
Although this type of post holder is great for fence posts in normal ground we would not recommend it for any type of fencing which puts lateral stress onto the posts. Chain link fencing for example, puts a lot of stress on the posts as it is tightened and the post holders would not be secured strongly enough in the ground for this. Once the spike is driven into the ground, the driving tool can be removed and the post pushed into the holder. There is a bolt on the side of the holder that can be done up easily with a spanner to keep the post firm in the spike.
If you want to put a fence post onto a patio for a summer house, gazebo or pergola there is a special bolt down post holder available for this too. It is shown on the left and as you can see it sits flat on the floor and is bolted or screwed down in all four corners.
On a concrete surface we suggest you bolt it down using Rawl bolts (shown above) which are placed into holes drilled into the concrete and then tightened. As the head of the bolt is tightened the bottom sheath expands, gripping the concrete. You can also use a chemical fixing to hold the post holder down with threaded bar studs that are set into the mounting surface. This is probably the strongest method especially in concrete which has been mixed by hand and may contain air bubbles.