How to fix Colorbond fence with widening gap?

dennislokw

My gate is keep open wider and wider. I ask fence specialist to have a look. They said the posts are all right and we just have to change the door, it will be fixed. However, the gate is still wider and wider. I don't think changing the door is a permanent fix. Do you guys have any idea? 
There are two specialists told me that they have never seen this before.

MitchellMc

Welcome to the Bunnings Workshop community @dennislokw. It's terrific to have you join us, and many thanks for your question about a Colorbond fence.

I think this is a fairly clear case of the support post moving. The gate hasn't changed size, so it indicates there is movement in one of the two posts. Given the setup, I would presume the post on the left has tilted outwards to the left, causing the gap at the top of the gate on the right. I can't see installing a new gate as a fix, as to cover the addition gap, you are going to need a gate that is not rectangular, and the panel will look odd.

The posts need to have a level placed on them to tell which one is not perpendicular to the ground and plumb. That post and footer need to be dug up and reinstalled so it is plumb. However, if the whole fence on that side is slanted, you might also need to replace the panel on that side if straightening the post does not allow it to be reinstalled into the channel.

Please let me know if you have any questions.

Mitchell