How to support leaning retaining wall and fence?

Question

Hi all,

A portion of the boundary retaining wall and fence above are leaning towards my backyard, likely caused by push from the tree on the other side in my neighbour's yard. It would be ideal to do a serious repair and get the neighbour involved but this might take time. In the meantime, is there any temporary safety measure I can take without touching the retaining wall and the fence directly, like installing a few independent support posts near the fence, in case there's a sudden collapse?

Appreciate your advice.

misudori432 · Answer

Thank you @JacobZ 😊

JacobZ · Answer

Hi @misudori432,

Welcome to the Bunnings Workshop community, it is wonderful to have you with us.

Given it’s a relatively low retaining wall, you’re generally not in the territory where engineering is required, but it’s still smart to think about safety while you sort things out with the neighbour.

One of the simplest temporary measures is to install some independent mid-span support posts to help restrain the retaining wall. You can concrete in a few timber posts at the midpoint between the existing posts and then drive galvanised batten screws of a suitable length through those posts into the retaining wall.

You want to make sure any posts are properly set in concrete so they can actually take some load if the wall shifts. If you aim to have the posts protrude 400-600mm into the ground, with a 300mm diameter of concrete around them, this will make them nice and solid to help resist any lateral force that is applied.

Longer term, it will need to be properly repaired with the neighbour, especially if the tree is contributing to the pressure, but these kinds of supports can help reduce the risk of sudden movement in the meantime.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob