The easiest way to avoid repainting the windows. When you wash the windows, maybe once a year? Every other year? Or more often/less often? At the same time, wash off the painted surface with a sponge/cloth. When everything is clean, open the jar of wax, use a regular kitchen sponge to apply the wax, very little is needed. (NOTE! Use white wax on white windows for best results!) Rub into all painted surfaces, both wood and putty. When you're done with the entire window, frame included, wipe off the excess. (don't forget to wet the paper/cloth afterwards!) If you do this between 1-5 year intervals, it will take a long time until you need to repaint the windows again. Darker colors wear more = need more frequent intervals Lighter colors wear less. Feel free to use white pigmented wax for white windows.