Hi,
I'm planning to add WPC cladding to cover my existing Colorbond fence. Since the WPC panels are a bit heavy, I'm thinking of building a standalone frame close to the fence, without attaching the panels or the frame directly to it.
I'm trying to figure out what size metal posts I need to use for the frame, but I haven’t been able to find any reference for this kind of project online. I read on a website that the joist spacing for WPC panels should be 450mm, but there’s no information about the spacing for the vertical posts.
By looking at the Colorbond Good Neighbour fencing panel weight and the load on each post, I thought 50x50 posts spaced every 1m might work.
This the draft i did for the project and this is one repeat of 10m long project

By looking at the guidline for Colorbond Good Neighbour fencing panel weight and the load on each post, I thought 50x50 posts spaced every 1m might work. The top and bottom would be connected by 20x20 beams, and for the middle section, I’m thinking of using this beam:

I would really appreciate it if someone could share their thoughts on this plan—whether it’s too much steel or not strong enough.
Note: I got the image below from the website https://heritonfencing.com.au for reference purposes.
