Austin patio and deck cleaning, done right.

A patio is rarely one material, and the mistake is treating it as though it were. Poured concrete tolerates real pressure. Flagstone, which is everywhere in this part of Texas, does not, because it is porous and soft enough to erode the face and blow out the jointing sand between pieces.

Composite decking has its own trap. It looks like the toughest surface out there and it is the easiest to ruin, because too much pressure lifts the surface fibres into a permanent fuzz that then holds dirt worse than before. Manufacturers are specific about maximum pressure for exactly this reason, and it is far lower than most people expect.

Wood decks need the same treatment as a cedar fence: low pressure, worked with the grain, solution doing the lifting.

The reason patios get bad faster than driveways is shade. A covered or tree shaded patio stays damp for hours after the surrounding ground has dried, and that is what algae needs. It is also why patios turn genuinely dangerous rather than just dull. A thin algae film on smooth stone gets slippery enough to put someone down, and it is worst right after rain when nobody is thinking about it.

That slip risk is the honest reason to clean a shaded patio on a schedule rather than when it starts to bother you visually.