Pressure washers glossary

Short, plain-English definitions of the terms you'll meet when choosing a pressure washing service provider in Columbia, SC.

What are tiger stripes on gutters?: Tiger stripes are vertical streaks of oxidation and discoloration that form on gutter faces, typically caused by UV exposure and dirt accumulation running down the metal surface.
What is a chemical wash?: A chemical wash applies specialized cleaning solutions to exterior surfaces to dissolve and lift dirt, algae, and stains before rinsing, minimizing pressure-based damage to delicate materials.
What is a cold water pressure washer?: A cold water pressure washer is a cleaning machine that forces unheated water through a high-pressure nozzle to remove dirt, debris, and stains from exterior surfaces.
What is a fan tip nozzle?: A fan tip nozzle is a pressure washer attachment that releases water in a flat, wide spray pattern and is rated by degree size (0, 15, 25, or 40 degrees) to match the cleaning task.
What is a hot water pressure washer?: A hot water pressure washer is a machine that heats water to 100-200°F and sprays it under high pressure to dissolve and remove grease, oil, and tough residue from surfaces.
What is a ridge cap?: Ridge cap shingles are the pieces that cover the peak or apex of a roof where the two sloped sides meet; they are exposed to sun and moisture and often show algae staining first.
What is a surface cleaner attachment?: A rotating flat-disc attachment mounted on a pressure washer that cleans large flat surfaces by spinning side jets, designed to prevent the uneven marks and streaks left by a handheld wand.
What is a surfactant?: A surfactant is a chemical compound that reduces the surface tension of water, allowing cleaning solutions to wet and penetrate surfaces more effectively to lift dirt and contaminants.
What is a turbo nozzle?: A turbo nozzle is a rotating jet tip attachment for pressure washers that spins at high speed to concentrate water force, delivering more aggressive cleaning than a stationary fan tip.
What is black streaks (gloeocapsa magma)?: Gloeocapsa magma is a blue-green algae that forms dark streaks and stains on roofs, thriving in shaded, moist environments and commonly removed with soft washing rather than high-pressure equipment.
What is downstreaming in pressure washing?: Downstreaming is a detergent delivery method in which cleaning solution is injected into the supply line before the pump operates, allowing low-pressure mixing rather than high-pressure injection.
What is efflorescence?: Efflorescence is a white, powdery mineral deposit that forms on concrete and masonry surfaces when salts are drawn to the surface by moisture and then evaporate.
What is GPM (gallons per minute)?: GPM (gallons per minute) is the volume of water a pressure washer pump delivers per minute; higher GPM means faster coverage and completion of larger surface areas.
What is gutter brightening?: Gutter brightening is a chemical treatment that removes oxidation discoloration, stains, and tiger striping from aluminum gutter systems to restore their original appearance.
What is oxidation removal?: Oxidation removal is the cleaning process that eliminates chalky, oxidized paint or metal finishes from exterior surfaces like siding and signage through pressure washing or chemical treatment.
What is pressure washing (power washing)?: Pressure washing is a cleaning method that forces water at high pressure (typically 1500-4000 PSI) through a nozzle to remove dirt, grime, mold, and buildup from hard surfaces.
What is PSI (pounds per square inch)?: PSI (pounds per square inch) is the unit of measurement for water pressure force in pressure washing equipment, indicating how much force water exerts per square inch of surface area.
What is rust stain removal?: Rust stain removal is the process of eliminating iron oxide discoloration from surfaces like concrete and pavers, typically using chelating agents designed to break down and lift rust deposits.
What is SH mix ratio?: SH mix ratio is the concentration of sodium hypochlorite (liquid bleach) mixed with water, expressed as a percentage or ratio, used to clean building surfaces without high pressure.
What is sodium hypochlorite?: Sodium hypochlorite is a liquid bleach solution used in soft washing to kill organic growth like algae and mildew on exterior surfaces.
What is soft washing?: Soft washing is a low-pressure cleaning method that relies on chemical cleaners, surfactants, and disinfectants rather than water force to remove dirt, algae, and stains from delicate surfaces.
What is upstreaming in pressure washing?: Upstreaming is the method of introducing cleaning chemicals at the discharge side of a pressure washer pump, allowing them to mix with pressurized water for application at full pump pressure.
What is wastewater reclamation?: Wastewater reclamation is the practice of capturing and containing runoff water generated during pressure washing work to comply with environmental regulations that restrict discharge to storm drains or ground.
What is wood brightener?: Wood brightener is an acid-based chemical applied after wood cleaning or stripping to neutralize alkalinity and restore the wood's natural color and pH balance.