Pressure washing is a versatile and effective cleaning technique that utilizes high-pressure water to remove dirt, grime, mildew, and other contaminants from various surfaces. However, there are different types of pressure washing, each with its own unique characteristics and applications. In this comprehensive guide, we will explore the various types of pressure washing, their recommended PSI and GPM for cleaning house siding and driveways, the chemicals used for organic stains and wood surfaces, and the key differences between power washing and soft washing.
Types of Pressure Washing
1. Pressure Washing
Pressure washing, also known as power washing, is the most common type of pressure cleaning. It uses an intense stream of water, typically ranging from 1,500 PSI to 3,500 PSI, to remove dirt, mildew, mold, and other contaminants from surfaces. This high-pressure water stream is effective in cleaning a wide range of surfaces, including concrete, brick, siding, and decks. While chemicals may be used, they are not always necessary for effective cleaning.
2. Power Washing
Power washing is similar to pressure washing, but it combines high heat and a pressurized stream of water to achieve a deeper clean. The high heat, typically ranging from 200°F to 300°F, helps to break down and dissolve stubborn stains, grease, and oil-based contaminants. Power washing is often used for commercial and industrial applications, where a more thorough cleaning is required.
3. Soft Washing
Soft washing, also known as low-pressure washing, uses a stream of water between 150 and 300 PSI, which is stronger than a garden hose but weaker than a typical pressure washer. This lower-pressure approach is effective for cleaning delicate surfaces, such as vinyl siding, wood decks, and fabrics, without causing damage. Soft washing requires the use of specialized cleaning solutions, known as soft washing cleaners, which are designed to break down contaminants and clean surfaces gently.
Recommended PSI and GPM for Cleaning House Siding and Driveways
House Siding
For cleaning house siding, a gas-powered pressure washer unit delivering at least 2,000 PSI of pressure with a flow rate of 3.0 GPM or greater is recommended for effective cleaning. This level of pressure and flow rate ensures that the water stream can effectively remove dirt, mildew, and other contaminants from the siding without causing damage.
Driveways
When it comes to cleaning driveways, a high-pressure washer with a flow rate of 3.0 GPM or greater is suitable. The high pressure and flow rate are necessary to break down and remove stubborn stains, oil, and other contaminants that may have accumulated on the driveway surface.
Chemicals for Organic Stains and Wood Surfaces
Bleach
Bleach is a common chemical used in pressure washing for removing mildew and mold from surfaces.
Caustic
Caustic chemicals, such as sodium hydroxide or potassium hydroxide, are effective in removing grease and oil-based stains.
Ammonia
Ammonia-based cleaners are used to remove dirt and grime from surfaces.
Potassium Hydroxide
Potassium hydroxide is a powerful cleaning agent that can be used to remove stubborn stains and dirt from various surfaces.
Soft Washing Cleaners
Soft washing cleaners are a specialized blend of water, bleach, and surfactants that are designed for use in soft washing. These cleaners are formulated to break down contaminants and clean delicate surfaces without causing damage.
Key Differences between Power Washing and Soft Washing
Pressure
Power washing uses high pressure, typically above 1,500 PSI, while soft washing uses low pressure, typically between 150 and 300 PSI.
Heat
Power washing utilizes high heat, while soft washing does not.
Chemicals
Soft washing relies on specialized cleaning solutions, while power washing may use various chemicals depending on the surface being cleaned.
Surface Suitability
Soft washing is safer for delicate surfaces like vinyl siding, wood decks, and fabrics, while power washing is better suited for hard surfaces like concrete and stone.
Technical Specifications
Pressure Washer
For professional-grade pressure washing, a gas-powered unit with a triplex pump is recommended. Triplex pumps are known for their durability, efficiency, and ability to maintain consistent pressure.
Flow Rate
A flow rate of 3.0 GPM or greater is suitable for cleaning house siding and driveways, as it ensures that the water stream has enough volume and force to effectively remove contaminants.
PSI Settings
Pressure washers can have multiple PSI settings, including low, medium, and high pressure, as well as mega high pressure for specialized tasks. The appropriate PSI setting will depend on the surface being cleaned and the type of pressure washing being performed.
By understanding the different types of pressure washing, the recommended PSI and GPM for specific cleaning tasks, the chemicals used for organic stains and wood surfaces, and the key differences between power washing and soft washing, you can make informed decisions and achieve the best results for your pressure washing needs.