Pressure washing or power washing is the use of high-pressure water spray to remove loose paint, mold, grime, dust, mud, chewing gum, and dirt from surfaces and objects such as buildings, vehicles, and concrete surfaces. The volume of a mechanical pressure washer is expressed in gallons or liters per minute, often designed into the pump and not variable. The pressure, expressed in pounds per square inch, pascals, or bar, is designed into the pump but can be varied by adjusting the unloader valve. Machines that produce pressures from 750 to 30,000 psi or more are available

• Soft Washing (House Washing) – Soft washing is a low-pressure cleaning process commonly used to safely treat and remove organic matter: mildew, bacteria, algae, fungus, moss, lichens in addition to dirt, grime, and spiderwebs. Soft washing originated as an alternative to power washing where high pressure can cause damage. The application is achieved from low pressure dedicated pumps where measurements of commonly used products, mainly sodium hypochlorite and detergents can be precisely metered and applied. Soft Washing continues to evolve. Pumps now available produce more pressure than original electric diaphragm pumps, allowing the solution to be safely applied at further distances and adding increased rinsing volume. Booster pumps, air diaphragm, and gas-powered diaphragm pumps. Metering systems, allowing precise metering and mixture of sodium hypochlorite, detergent, and water. Color marking detergents available to show where the mixture has been sprayed, reducing usage while assuring proper coverage. Remote systems to switch between applying solution and rinsing. Neutralizing agents to aid in reducing damages that can be caused by chemicals. Soft washing has drastically changed the proficiency and safety of cleaning structures and roofs.

• Roof Washing – Roof cleaning is the process of removing algae, mold, mildew, lichen and moss from roofs. Also cleaning oxidation on metal roofs. Cleaning can extend the duration of a roof’s ability to function. Algae and other types of build-up often form on the north and west parts of roofs that are shaded or receive less sun, and can reduce a roof’s life expectancy. The presence of soot, dirt, or biomass can affect how much sunlight is absorbed by a roof and thus the amount of heat a building absorbs.