is formed from a plurality of overlapping boards 14 each with a side surface 16 and an under surface 18 boards 14 may be formed of wood vinyl aluminum or fiber cement and may have different profiles for example as shown in fig2 the profile is that of alcoa silhouette classic double 5 lap extruded vinyl siding 12 in fig3 the profile illustrated is alcoa silhouette classic 4 and in fig4 the profile is that of alcoa silhouette classic dutchlap double 4 5 the term u201c double lap u201d indicates that the extruded siding simulates two boards while the number e g u201c 5 u2033 u201d in the case of classic double 5 refers to the width of each board while specific profiles are shown in the drawings it will be understood that scrubber 10 may be adapted to cleaning other lap siding profile 12 and to siding manufactured by other companies as best seen in fig2 5 scrubber 10 includes an elongated base 20 which may be formed of wood metal or polymer construction such as pvc elongated base 20 has a bottom surface 22 a top surface 24 sidewalls 26 and generally blunt upper and lower ends 28 30 respectively with side and end edges rounded if desired as illustrated elongated base 20 may be about 12 18 inches long and about 1 inch wide such that upper and lower ends 28 30 of elongated base 20 overlap a double run of lap siding 12 as shown in fig1 4 elongated base 20 may be longer such that it overlaps three or more of boards 14 but at some length scrubber.