When Do Steel Fence Posts Fail?

Regardless if you are the owner of a residential, commercial or industrial fence, this blog post might be helpful for you. Why? Because if the fencing material used is steel, your fencing is likely supported by steel posts. Thus, in the following post we will discuss when do steel fence posts fail.

There are several reasons why fencing posts fail. Some of them include structural fails, soil movement and post-pull-outs. Structural failure is quite common. It happens if unsuitable fencing material has been used, resulting in design or installation failures. When it comes to soil movement, it simply means that the load of the fence cannot be supported by the soil. It does not have the strength to do so. Sometimes you will also come across posts that have pulled out. The reason behind it is incorrect installation – the posts are not set deep enough.

Australian made steel fencing

Corrosion and why steel fencing posts fail?

Steel fence posts fail for many other reasons. It can be simply by choosing the incorrect thickness of the gauge post. It is important to remember that fence posts are usually the most labor-intensive portion of the fencing project. The thicker the steel post, the more likely it will add extra years to the fencing lifespan.

However, there is one major factor when it comes to steel post failure. It is corrosion! It is common to discover that your steel fence posts have corroded at the base. The reason is most likely an incorrect installation that has lead to premature failures that, in turn, leads to an expensive fence (gate) repairs.

We should be familiar with corrosion. However, here is just a quick reminder. Steel corrosion, regardless of the environment it is in, is an electrochemical process. It is a complex process and depends on various factors. For example, structure or composition of the steel, impurities, or unevenly distributed internal stress. This process requires the simultaneous presence of moisture and oxygen. In essence, the iron in the steel is oxidised to produce rust. How fast will corrosion take place? It depends on many factors. The main one is the micro-climate surrounding the steel fencing.

How to Repair Rusting Sports Fencing Posts

How to prevent steel fencing posts from failing?

Choosing the suitable material for your fencing posts is the right place to start. Using galvanized steel posts can add many years to your fence. However, the lifespan of galvanized steel posts also varies. The Australasian Wire Industry Association has advised that the durability of galvanized steel posts can range from 3 to 50 years. This is a considerable variation. Coastal areas are more prone to corrosion as salt water is an electrolyte, which speeds up rusting.

According to the Australasian Wire Industry Association:

“a simple rule of thumb is AS/NZS 4792 HDG300 galvanized posts will last 3 times longer than AS/NZS 4792 ZB100/ZB100 pre- galvanized posts, while batch galvanized posts to AS/NZS 4680 will last 5 times longer than pre-galvanized posts in the same environment.”

Once you have chosen the suitable fencing material for your posts, the next step would be the correct installation process. For example, if you are installing sports ground fencing or the fencing expert is doing the installation work for you, the concrete (if the concrete is used) must be domed around the posts. It will eliminate the water gathering (pooling) around the fence posts. It is essential for sports ground fencing because the ground (if natural grass) is frequently watered, creating much higher climatic corrosion levels.

If you are in between whether to have the concrete bed or not, then remember: concrete beds prevent contact between soil, moisture, and the bottom of the fencing post. Concrete beds might have higher installation costs. However, in the long run, it is a financially wiser decision. It will eliminate the need to replace prematurely rusting fencing posts.

Installing New Fence Or Gate Posts