Now the days are longer and the weather warmer are you planning some fence work? If you are reading this, you may be thinking about using timber fence posts and be wondering how FenceFins work to hold them in place?
There are several advantages to wood posts. Firstly, they look nicer and more garden-friendly. Nowadays most timber posts are treated for rot and so will last a good ten years or more in the ground. Secondly, they weigh far less than concrete posts so are much easier to manage.
But traditionally the way to anchor fence posts in the ground is to use either concrete or metal spikes. Unfortunately neither gives a particularly attractive finish or are very easy to use.
Concrete stops you planting up close to the post. You have to dig a large hole and lug a lot of concrete around. Makers often recommend one, or even two, 20kg bags per post. With spikes, the box fixing is visible above ground (and may rust, in time). To install spikes you have to drive them deep into the ground. Doing this with a sledgehammer is very hard work, the spikes can easily go in at an angle leaving you with a fence post that isn’t properly upright. Also, it is difficult to get the distance between posts to fit the fence panel.
FenceFins solve problems
So now you’ve found FenceFins.
If you’ve seen our website you will know that with FenceFins there will be far less heavy work involved in getting your fence post quickly and easily installed (see our How to Use pages here, or watch the video).
FenceFins will be invisible too, as they sit just below ground level. And you can plant right up to your fence post.
But, you may think, I can’t see how those thin pieces of metal can hold my fence post up. So bear with me as I explain how FenceFins work so well.
How FenceFins work – the technical bit
First, think about the forces trying to push the fence over. The only force is, of course, the wind. The wind pushes on a large area of fence panel (think about a boat sail).
So this force has to be resisted by something in order to stop the fence blowing over. The only thing holding the fence in place is the fence post. It, in turn, is held in place by the soil. So, the logical thing is to make sure the post has a sizeable enough area that pushes against the soil to stop the fence post from moving.
Hard to picture that? Imagine you had driven a space into the ground. Now you want to move it forwards and backwards through the soil. It would be incredibly difficult. That is because you have to push the whole surface area of the spade’s face through that soil. That is the way that FenceFins work. They present a large surface area that pushes against the soil and cannot be easily moved.
There is a little more technical explanation around why FenceFins work best if they sit just under ground level with a length of post below and why their distinctive A-shape is so important, but basically that’s how FenceFins work.
So, how do other fence anchors work?
If you think about it, this is how concrete works too. You have to dig a large hole and use a lot of concrete because you need a large surface area of concrete to press against the soil. The fact that the concrete is also heavy is not really very valuable as there is not much uplift force on a fence (so you really don’t have to weight it down!). All that weight does is to make it really difficult to lift out your fence post at a later date!
Having seen the importance of a sizeable surface area it is worth thinking about how spikes work since they are quite slim and don’t present much surface area to the soil. So spikes need to be driven a long way into the ground to overcome this lack of area.
I hope this short article has helped you to picture how FenceFins work and reassure you that those ‘thin bits of metal’ that are so easy to handle and install really will hold your fence securely.