This is an issue for the paint industry to clear up, rather than the low-voltage industry. One paint association technical representative responding to my inquiry on this topic stated that water-based paint and primer should “not pose any problems.” On the other hand, he did not flatly state that other paints based in oil, epoxy or other nasty stuff, does also not pose any problems. While this issue gets fine-tuned, be sure to charge a fair and reasonable fee to change any wiring the owner is being told “needs” to be replaced because they painted it. As it stands now, the blanket statement: “painting exposed wire ruins it,” is an urban legend that needs to be addressed by the paint industry, in an official manner. I will go out on a limb and publically state...No one should complain about water-based paint on jacketed cables since the actual wiring insulators would be protected by the overall jacket from any un-likely effects of the water-based paint. Until this paint thing gets decided don’t even think about staining!