I did my basement floor about 45 many years back when house was new and we just moved in. I washed it and etched with Muriatic acid and washed off. Haven't needed to repaint considering that with it's possible a dab below and there. Another choice for the strip outside http://industrialgradeepoxyfloor55421.mpeblog.com/16538939/the-best-side-of-epoxy-floor-paint-over-painted-wood