How to fix sinking slab?

[meldarl]

Hi Everyone,

I could use some advice. Do you think this is a DIY job, or should I call a professional? I’m a bit concerned that the slab might be sinking, which could cause bigger issues.

Thanks in advance!

[EricL]

Hello @meldarl 

Thanks for sharing your question about your sinking slab walkway. It's possible that water has gone under the slab and has softened the soil making it settle. When the soil settles the concrete slab goes with it. I recommend looking around your property and see if any of the storm drains are flowing around that area and is going under the slab. Another possible cause is that water has been slowly flowing to that open section of the slab and has been slowly through time softening the soil beneath.

If this has only recently happened odds are that a great deal of water is passing under the slab. But if this has been happening slowly, it's possible that water is slowly flowing through the cracks of the cement slab. I suggest having a quick look at this guide - How to fill a joint in a concrete slab by @JacobZ. It could possibly slow down the entry of water under the slab, but unless the actual source of water can be stopped the slab will continue to settle.

Another option is to engage the services of a concrete slab specialist. they might be able to pinpoint where the source of water is coming from, and they can suggest ways to raise your slab back to its original position. 

If you have any other questions we can help with, please let us know.

Eric

[meldarl]

Thanks @EricL for sharing the guide. There was a condensation line from our instantaneous water heater nearby, so I’ve extended it away from the property.

I’m hoping this isn’t something that requires an urgent fix?

[EricL]

Hi @meldarl 

You'll need to observe your slab for a while and see if it continues to sink. If it does continue to sink within the next few weeks, it might be time to consider having it repaired.

Eric