How can I fix the outdoor uneven concrete?

[easymode]

Hello guys, I have a concrete sidewalk at the back yard. Because of the tree roots, I guess, the concrete are uneven now (photo attached). I am going to apply new concrete on top of low area. What kind of product/cement do I need? Or is there any other better solutions to fix this uneven joints? Thanks in advance.

[Jason]

Hi @easymode,

Welcome to the Workshop community and apologies for the slow reply. We're looking forward to reading all about your projects and plans. Feel free to post anytime you need a hand or have something to share. 

Have you considered removing and replacing the high segment? And has the tree that caused this issue been removed?  

Jason

[MartyH]

You might want to hire a demolition (jack) hammer to remove that high section. 

[MitchellM]

@easymode How big are these slabs? The framing of the photo doesn't tell me. I'd agree with Jason's response, personally I would break up that slab, find out what's going on with the roots then re-pour that slab.

Problem with raising the level of the others is, if that slabs going to continue to rise and if it has only risen on that one corner/side, even if you raise the others it will still remain wonky.

[easymode]

Thank you guys, @Jason @MitchellM @MartyH . I have not checked my account and sorry for the late response. The tree is no longer there any more. Actually, the "High" part on the photo is the normal level. The "Low" part should be up to match with the "High" part. I was thinking to either use "fast set cement" or "MaxPro pebble resurfacer". I am not sure if these products are bond with the old slab. 

[MitchellMc · Accepted solution]

Hi @easymode.

Glad to see you have got the tree situation sorted and the cause resolved. If you are bringing the low portion up to match the high portion, I would recommend the use of Dingo 20kg Hi-Strength Concrete, with the addition of Bondcrete applied to the surface before pouring. I am recommending concrete over cement, as there appears to be a significant difference in height and the aggregate will assist in the new pour not cracking. The Bondcrete is painted over the existing slab and will help the concrete in binding to the old surface.

If you wish to have a pebblecrete effect, I would use that product over the top after you have fixed the level of the slabs with concrete. The MaxPro pebble resurfacer is a coating and is not specifically designed to adjust levels. The concrete is also a significantly cheaper option.

If you have any further questions, please let me know.

Mitchell

[easymode]

Thanks @MitchellMc , I will follow your advice and try the click & collect tomorrow. Looking forward to post my final photo after finish.

[muhsin]

Hi MitchellMc

Many thanks for the posting. How long should i wait after the Bondcrete before Dingo is appllied please? thank you 

[MitchellMc]

Welcome to the Bunnings Workshop community @muhsin. It's wonderful to have you join us, and many thanks for your question about applying Bondcrete.

You should apply the cement product whilst the Bondcrete is still tacky. Somewhere around 30min after application would be about right, but if it's a hot day, then it could be sooner.

Please let me know if you have further questions.

Mitchell