An extendable soft brush to clean with (two buckets; one with solution and one with rinse water; a bit of Calgon liquid water softener in each). Garden hose with twist sprayer. I wet the sides of the trailer before doing the roof.
I prefer to get on the roof but I know AS owners have an unreasoned fear of such. Use shoes that won't slip.
1990 35' Silver Streak Sterling
; 9k GVWR.
2004 DODGE Cummins 305/555; 6-manual; 9k GVWR.
Hensley Arrow. 10-cpm solo, 18-cpm towing
Sold: Silver Streak Model 3411