How to level external concrete surface?

[Grant123]

Hi,

I would appreciate some advice on the best product to use to level an external concrete surface?  

I have uploaded an image for reference.  The length of concrete to be worked on is 140cm, sloping from 0cm (at the visible crack line) to a depth of 7cm (at the adjoining wall).  The width of the concrete slab is 32cm.

Any advice on how best clean the existing surface (paint) before applying the product would also be much appreciated.

Once the concrete surface is level and cured, I intend adding a fence on top, which will be bolted into the surface.

Thanks.

[EricL]

Hello @Grant123 

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about levelling your external concrete surface.

I propose cleaning the surface with a pressure washer to drive out any mould or mildew that might have settled on its surface. I then recommend washing the surface with Berger Jet Dry 1kg Active Etch. It preps the surface of the concrete without using harmful chemicals. Plus, it's rinse residue will not harm plants or grass.

Once the surface is totally dry, I suggest using Dingo 20kg Self-Levelling Cement. I recommend building a bit of formwork on the other side of the concrete surface to hold the new concrete in place. I also suggest drawing a guideline on the form work so that you can see how far you'll need to fill and form the concrete.

Please keep in mind that the thin part of the concrete might be prone to splintering so it's best to slow the evaporation down by covering it in plastic. It might delay the drying time, but the concrete will cure properly without forming cracks. Once the concrete has fully cured you can then drill through it to install your fence post.

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

Eric

[Grant123]

Hi Eric,

Wow, what an awesome response, much appreciated!  I have been racking my brain on google searches and ended up with a serious case of information overload before turning to this workshop.  Your advice sounds great and I will be following it to the letter this coming weekend.  I particularly like your suggestion on using plastic to slow the evaporation down on the thin part of the concrete.  

Cheers,

Grant

[Grant123]

Hi Eric,

Thanks again for your suggestions, which ensured a job well done - pic below.  Even my dog loved it and left some paw prints   Luckily the cement had pretty much set by then and paint will leave no trace lol.

Cheers,

Grant

[EricL]

Hi @Grant123 

Thanks for sharing that update, that looks very nicely done. There is nothing like having the pups seal of approval with a couple of paw prints thrown in. I look forward to seeing the fence installed.

If you need further assistance, please let us know.

Eric