Acid etching? These guys may be able to point your further... Landscape And Architectural Design Products PL

Not many paints adhere to these sort of surfaces long term most tend to wear on the leading edges exposing the old surface. your best type of paint finish would be industrial grade floor finish but preparation will still be the key. You could also look into a concrete stain.

Hi Wren, what a lovely setting! I would be inclined to match the door colour in with the exterior wall colour. Include the casing, threshold and trims as well and this way you will end up with the timber, black and your main paint colour to give a better sense of balance. Good luck! Regards, Kathryn.

Hi Liz, I understand your concern about waterproofing. I guess it depends on who does it. I'm extremely thorough. The last time I waterproofed I read every piece of technical information from the suppliers. When I went to order the materials, I asked for things that even the suppliers did not know was in the recommended procedure. I'd warrant my own detailed waterproofing over some tradie in a rush to get to the next job. Not saying they are all like that, but I value and trust my own approach as well. In terms of a certificate, a workaround for a through DIY job is to take detailed photos on installation, similar to what a Building Certifier would be looking for on inspection (not that we can rely on Building Certifiers nowadays either)!!!! My point is that a certificate does not necessarily guarantee a thorough job. Just ask the apartment owners at Mascot..... PS Liz good point on the visibility of a clear 50mm threshold, versus a barely visible one where the toe can scuff...