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How much weight can a steel post hold?

Just Starting Out

How much weight can a steel post hold?


Im trying to build a steel fence gate but I found I have many many many questions not sure, hopefully anyone would give me a hand.

My fence gate is 1.8m height, 1.5m width and approx. 50kg. I got a square 50mm steel post and 1.8m height, my questions are:

1. does this steel post hold my gate safely?

2. when installing the post, what's the difference between put it in-ground and setup on top of concrete slab? I prefer set on top of concrete but don't know which one is more secure.

3. how much deep of post hole for a 1.8m steel post? I tried digging a hole last time, I digged about 800mm then I found clay soil that water cannot drain, do I need to continue digging or it is okay to setup in clay soil?


Really thanks for any reply!



Kind of a Big Deal

Re: how much kg can a steel post hold?

I don't have the technical data sheet for you to answer the question but it will be important to know the thickness of the steel post also @szp895 

Handy and helpful
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Bunnings Team Member
Bunnings Team Member

Re: how much kg can a steel post hold?

Welcome to the Bunnings Workshop community @szp895. It's great to have you join us and many thanks for your questions.


It's fantastic to see @ProjectPete is on the case ready to help you out. If you can tell us the product you are using or the thickness of the wall and dimensions of the post then it would help us in providing an answer.


I haven't personally seen a setup for on top of a concrete slab for a steel post which is designed to bear the weight of a gate. Once again, if you could illustrate the product you've seen I could advise on its suitability. However, I would imagine the post concreted into the ground would be a more secure option than a mount above the concrete.


I can't imagine you would need to dig a footer deeper than 600mm for a gate weighing 50kg.


We look forward to you providing additional information and finding a solution to hanging your gate.




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