Sand and cement Render with Sika 1

[jdlittle91210]

Hi, My plasterer has just rendered an exterior wall with sand cement and Sika 1 as a waterproofing additive. I now need to paint the exterior wall and need to know what paint I can use and whether it needs stabilising first.The plasterer reckons the render would be classed as silicone based but from what I have read about Sika 1 this might not be the case. The rendered wall was the side of a block wall single skinned that was allowing rain to soak in and ruin the internal walls due to the porosity of the block.
Can any body point me in the right direction here thanks...