Rendering over smooth bricks

[Justin Bodley]

Hi,

I need to render an outdoor retaining wall. However the bricks are very smooth (I think they might be engineering bricks) and I'm not sure how well the render would adhere to it. I was thinking of screwing some galv expanding mesh onto the wall before rendering. Or could I score some lines with a diamond disc in an angle grinder? Any other ideas would be welcome. On a tight budget so I'm thinking of the cheapest but workable answer. Thank you in advance!!

 

[dontbelieveawordofit]

https://www.screwfix.com/p/sika-rendagrip-external-render-bonding-agent-red-10ltr/8831p
or.
sand /cement /sbr slurry painted on or flicked on with a tyrolean gun to create a key. also you could rake out any loose or suspect areas of mortar in between the brickwork to create a key in between the brickwork for the render.
ground in grooves will also help.
make sure you have weep holes in bottom of the wall .