Forbes states that while home sellers fail to look at the health of their roof, home buyers always take it into consideration before making a purchase. But by investing in a professional roof cleaning solution, you can quickly eliminate stains and boost your curb appeal.

dirty roof tiles next to clean roof tiles

Your roof plays a critical role in your home’s structural stability and aesthetic. Some ways to wash it are more common than others. Regarding low-pressure vs. no-pressure roof cleaning services, does it matter which one you choose? Absolutely, and our guide below explains why.

What Is Low-Pressure Roof Cleaning?

Low-pressure roof cleaning uses a pressure washer with moderate PSI to scrub rooftops. A typical power washer blasts water between 1,300 and 2,800 PSI (pounds per square inch). But low-pressure washing techniques use less than 1,000 PSI.

When performing low-pressure roof cleaning services, the technician will first cover the shingles and tiling with safe cleaning chemicals. Then, the specialist will rinse the roof using low water pressure.

Low-pressure washing techniques are efficient, safe, and ideal for extending the lifespan of roofing shingles. The combination of chemicals and low water pressure effectively remove:

  • Gloeocapsa magma (to prevent algae discoloration)
  • Dirt buildup
  • Mold, mildew, and moss growth
  • Black stains
  • Insect and rodent nests

Is Low-Pressure Roof Cleaning Safe for All Roof Types?

Low-pressure washing uses gentle products to remove debris buildup from roofing tiles. The Asphalt Roofing Manufacturers Association (ARMA) considers it a safe cleaning approach for a variety of roofing materials, including:

  • Concrete
  • Ceramic
  • Asphalt
  • Fiberglass
  • Wood
  • Metal
  • Rubber
  • Slate
  • Barrel

What Is No-Pressure Roof Cleaning?

No-pressure roof cleaning (also referred to as chemical washing) allows technicians to clean a roof without water. A company uses chemical solution mixes to extract dirt, mold, and debris from shingles and tiles. The entire process takes less than an hour to complete (depending on the roof size). No-wash techniques primarily utilize:

  • Sodium hydroxide
  • Sodium hypochlorite
  • Sodium percarbonate

The chemical solution isolates and dissolves organic matter without the need for water. It separates mildew and algae spores from tiles and then eradicates them. No-pressure roof cleaning solutions also leave behind a protective film to deter future mildew, moss, and algae growth.

Is No-Pressure Roof Cleaning Safe for All Roof Types?

A key advantage to no-pressure roof cleaning is that it does not produce runoff because it does not use water. Chemical solutions are applied directly to the roof, where they work rapidly to dissolve harmful particles.

That being said, not every roofing material type can withstand a chemical treatment. Examples of substances that cannot endure chemical cleanings include slate, clay, concrete, and wood tiles. The agents in the solution mixtures are too abrasive for the materials, causing discoloration and deterioration.

To be safe, always check with an experienced home improvement specialist or roof cleaning technician to ensure the process is safe for your tiles.

Low vs. No-Pressure Roof Cleaning: The Pros and Cons

No-pressure chemical washes are fast to perform and effective in killing and preventing the future growth of algae, mold, moss, and mildew. They do not use water and therefore do not produce runoff. Chemical washes also leave behind a protective layer that hinders mold and algae from regrowing.

However, the chemicals used in no-pressure roof cleaning techniques can be too abrasive for specific roofing materials. Therefore, it’s best to double-check the solution won’t damage your tiles before choosing this cleaning approach.

On the other hand, low-pressure cleaning uses gentle, biodegradable cleansers and moderate PSI levels to wash dirt buildup, black stains, and particles away. It is a safe technique for the majority of roofing materials. On the downside, this process might not remove tough stains, and the prices tend to be higher than chemical cleaning treatments.

Low vs. No-Pressure Roof Cleaning: Difference in Costs

Many homeowners consider the difference in costs when electing to get professional roof cleaning services. But the price for any roof washing service can depend on:

  • The size of your roof
  • The severity of your stains
  • The time of the year (higher demand leads to more expensive rates)
  • Your roofing material (certain types of shingles may require specialized techniques)
  • Your location

Low-pressure washing requires chemical solutions, a pressure washer, and an experienced technician. The average cost for the cleaning service falls between $0.30 and $0.70 per square foot.

No-pressure techniques require fewer materials and time, therefore making them a cheaper alternative. A typical session only requires chemical solutions and an experienced technician. Since the service is quick (less than an hour), most no-pressure washes cost homeowners between $0.20 and $0.30 per square foot.

Let Your Local Roof Cleaning Experts Handle Your Home

If your roof needs some TLC, let a home improvement professional help. A professional roof cleaning specialist from First Coast Home Pros can inspect your roofing materials, offer pro tips, and suggest the safest and most effective way to clean your tiles.