Rendered Front Wall - Design Issue

Hi everyone

I'm after a bit of advice, my house has been undergoing refurbishment and will be finished with Weber Pral M (chalk colour) with Cedar cladding.

I want to do the front wall to match, and will have a low level blockwork wall built with 3 piers, and Cedar slats to make a screen inbetween the piers, something like this (colour will match the chalk render, not grey) -

View attachment 19742

If I done this in the Weber should it have some waterproofing like coping stones...

Rendered Front Wall - Design Issue