There are lots of folks that do use power washers. I don't. I use power washers on my farm equipment and my deck and know the damage that they can do from a moment's inattention, even on "low power". I won't risk damge to the sealants or decals just for the sake of ease. Once you undermine the sealant, even slightly, water seepage will make the sealant fail faster over time. If you start to peel a decal, there is no "gluing" it back down effectively without making matters worse... There are those that also advocate their use on roofs...again, a personal choice (risk). I'm the low-tech scrub brush and bucket type of guy when it comes to potential self-inflected damage because I "fell asleep at the switch" or got distracted for some other reason and "blasted" a hole in the rubber membrane or blew the sealant off the skylight
A regular hose, a brush on a long handle (actually I use a B&D power head brush-very effective and easy on the TT) and a bucket of cleaner with regular hose pressure to rinse. Guaranteed no additional damage above normal wear and tear...
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