Soft washing refers to the process of using a soft washing system to remove dirt and contaminants without high water pressure. Many of us are familiar with pressure washers, which are commonly used to wash exterior surfaces such as driveways, sidewalks, and siding.

However, pressure washing can be damaging to the surface being cleaned due to the immense pressure required to remove some dirt and grime.

Soft washing uses a system of water pressure reducing components and chemicals to safely remove surface grime without the potential for damage that often accompanies high water pressures. Today we will discuss in more detail what soft washing is, what it does, and when it is typically used.

What Is a Proportioner Valve?

If you are researching soft washing systems, you will quickly encounter the term proportioner valve. These valves are specially designed to allow chemicals such as detergents and surfactants to be combined with each other in various proportions. These chemicals are then mixed with water and applied to a surface using very low water pressure.

These proportioner valves can be used alone or in conjunction with other components such as ball valves to completely control the mixture of chemicals and water to fit the application. Proportioner valves are available in several sizes and configurations, depending on the system design and intended use.

Why Would I Want to Use Soft Washing?

Soft washing allows delicate surfaces to be cleaned without fear of damaging the surface. Exterior dirt and grime tend to accumulate, and removing them can often require invasive cleaning.

Surfaces such as concrete, brick, stone, and siding are generally durable enough to withstand standard pressure washing. These materials can often be cleaned using nothing but water applied at very high pressures.

This does not apply to all exterior surfaces, however, such as a fiberglass/asphalt roof.

Did You Know

Fiberglass/asphalt shingles are probably the most common residential roofing material in use today.

These roofs are very durable, simple to install, and include small bits of gravel and other components to resist UV damage and strikes. In some instances, rust (from deteriorated galvanized flashing) and tree sap can stain a fiberglass/asphalt roof and cause discoloration, sometimes leading to roof damage.

Cleaning off these contaminants can be troublesome however, as these stains are often deeply embedded into the gravel and other materials, making them difficult to remove without force.

Therefore, pressure washing is not recommended to clean these surfaces, as it can accidentally remove enough material from the shingle to drastically shorten the lifespan of the roof. This is a perfect example of when soft washing is the preferred solution.

How Does Soft Washing Work?

Soft washing usually employs a system of valves, hoses, and chemicals to deliver water at pressures often below that of the public water supply. In some situations, even public water supply pressure would remove the gravel and other components of a fiberglass/asphalt shingle, especially if the roof is nearing replacement age.

Soft washing essentially replaces the force of water with chemical reactions, loosening the dirt and grime, which is then very gently rinsed away. These systems can be assembled or purchased as a kit and can often be customized for the project.

Chemicals such as fungicides, surfactants, and bleach are commonly mixed in very accurate, customizable proportions to create a cleaning solution that gently removes the contaminants. After applying the solution, often only a gentle rinse is required.

Can I Buy a Ready-Made Soft Washing System?

Yes. Most soft water cleaning systems are available as a unit ready to install, or as a kit. These systems are relatively simple to use, and with practice can be used to clean various surfaces without fear of damage. These systems generally require a thorough understanding of the process, so for those new to the practice, a kit is often recommended.

Using a kit generally makes the process faster, as all of the components needed to complete the project are provided in the kit. In many situations, the homeowner is solving a common problem, so a standard soft washing kit or system will perform well in most circumstances.

That doesn’t mean, however, that a kit is the only option available to a homeowner. Most do-it-yourselfers with a few tools and plumbing experience can also purchase the separate components and build a system from scratch. These components usually include a tank(s) for storing the chemicals, pump, hoses, and a delivery method, such as a trigger gun and nozzle.

Is Using a Soft Washing System Complicated or Difficult?

Soft washing systems are not particularly difficult to operate, but it is important to follow standard precautions. Since these systems use chemicals, a thorough understanding of how to mix the chemicals is important. Many solutions will involve some sort of fungicide or surfactant to remove algae and other biological materials.

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These chemicals can be dangerous if used in strong concentrations and can result in personal injury. Therefore, safety precautions should always be in place, such as eye, respiratory, and skin protection.

In addition, many soft washing systems are used for the primary purpose of cleaning a shingle roof. As mentioned earlier, standard pressure washers are usually fine for cleaning most exterior surfaces, but not for fiberglass/asphalt roofs.

This often means that the user of the soft washing system is not just on a roof, but a wet roof. For this reason, many professionals will start a soft washing project on the low side of a roof and work their way to the top. Although it may seem counterintuitive, this method is often safer, because the user is usually standing on a dry surface.

Why Would I Care If My Roof Is Dirty?

There are a few reasons to consider cleaning a dirty roof, including extending the life of the roof and reducing potential health hazards. The visual appeal of a clean roof is obvious, but a clean roof is also more functional than a dirty one. Here are a few common issues caused by a dirty roof:

Roofs are notorious for mold and algae buildup, especially if there are large trees nearby providing shade. Birds and storms drop other debris onto a roof, which will eventually make its way into the gutters. If this debris is not intentionally removed, the result is often clogged downspouts. In most situations, these clogged downspouts force the gutters to overflow, dropping large concentrations of water very near the foundation of the structure.

This falling water can cause deep ruts in the landscaping, which can prevent water from running away from the foundation, causing foundation soil erosion.

Roofs with a significant amount of dirt, algae, and mold are also less efficient at dissipating heat, because the heat gets trapped between the roof and the contaminants. This can lead to increased utility bills as the HVAC system must work overtime to overcome this additional heat buildup trapped in the attic.

Soft washing the roof allows the shingles to breathe as they were intended and remain dry, greatly extending their useful life. 

Moldy roofs can also affect the health of the occupants of the structure. As mold and mildew are allowed to accumulate, they absorb the moisture needed to live. This in turn allows the roof to hold more moisture than it should, which aids in the growth of more mold and algae.

In large concentrations, this can affect the health of those sensitive to mold and mildew spores. Because soft washing often relies on surfactants, cleaners, and fungicides to remove the mold and mildew, any residue left behind can retard their future growth and provide a healthier environment.

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Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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