At least half the time (so it pays for itself). I figure we had maybe 5-6 hours into it. The big advantage to the surface cleaner is the consistent distance your keeping the washer jets away vs. by hand with a wand - so you don't hurt the wood...another plus is that you stay pretty dry as there is very little splash-back...one drawback would be it can't reach into edges/corners (i.e. the housing is larger than the jet diameter) so you have to use the regular wands there (no big deal). You can get just as good results with a regular wand, the surface cleaner just got it the job done much quicker.