About Pressure Washers for Decking
Aim for 100–130 bar at 6–8 L/min and stick to a 25° fan nozzle or surface-cleaner attachment. Never use a turbo (rotary) nozzle on softwood — it will pit and gouge.
Best picks: Kärcher K4 Power Control (with Wood mode), Nilfisk Core 125 and Bosch UniversalAquatak 135 — all gentle enough for soft pine while still lifting algae.
For composite decking, drop pressure further and follow the manufacturer's max-PSI guidance. Always pre-treat with a deck cleaner to dissolve the algae rather than blasting it off.