This informal CPD article, ‘Softwashing Techniques – Best Practices for Superior Cleaning’,was provided by SoftWash UK, who offer professional softwashing services. They are committed to advancing the field of softwashing through continuous innovation, education, and reliable customer service.
Introduction
Softwashing is a highly effective method for cleaning exterior surfaces, particularly those prone to organic staining caused by algae, mold, mildew, and lichen. Unlike pressure washing, which relies on force to remove dirt and growths, softwashing uses specialized chemical solutions to break down contaminants at their source. This ensures a deeper and longer-lasting clean while reducing the risk of surface damage.
However, achieving optimal results depends on using the correct techniques, application methods, and safety precautions. A poorly executed softwash can lead to uneven cleaning, surface damage, or environmental contamination. This guide outlines best practices for softwashing, from surface assessment to post-cleaning care, ensuring efficiency, safety, and effectiveness.
Step 1: Surface Assessment and Preparation
Before applying any softwashing solution, it’s crucial to assess the surface to determine the appropriate chemical mix and application method.
Identify the Surface Type
Different surfaces require different chemical strengths and dwell times:
- Concrete & Brick – Can tolerate stronger solutions and longer dwell times.
- Render & Painted Surfaces – More delicate, requiring lower concentrations and shorter dwell times.
- Roof Tiles – Require careful application to prevent lifting or damaging protective coatings.
- Wood & Composite Materials – Softwashing is ideal for removing organic stains without causing warping or erosion.
Conduct a Risk Assessment
Before starting, inspect the site for potential hazards, including:
- Nearby vegetation – Pre-wet plants and grass to dilute any chemical exposure.
- Pets and pedestrians – Ensure safety measures are in place to prevent exposure.
- Drainage and runoff – Plan where excess solution will go to prevent contamination.
Preparation and Protection
- Remove loose debris such as leaves or dirt before applying chemicals.
- Cover delicate areas like flower beds, painted surfaces, and nearby windows.
- Pre-wet surfaces if necessary to control absorption and prevent excessive chemical reaction.
Step 2: Choosing the Right Chemical Mix
The effectiveness of softwashing depends on using the correct chemical dilution ratios. The wrong mix can result in an ineffective clean or surface damage.
Sodium Hypochlorite (NaOCl) – The Primary Cleaning Agent
- Used to break down organic growth, algae, and black spots.
- Typically diluted 3:1 (water to chemical) for deep stains.
- Effective on driveways, render, roofs, and fences.
Biocides – Long-Term Protection
- DDAC (Didecyldimethylammonium Chloride) is a key biocide used in softwashing.
- It prevents regrowth of algae, mold, and lichen for an extended period.
- Ideal for low-maintenance, long-lasting cleaning results.
Surfactants – Enhancing Effectiveness
- Surfactants help the solution adhere to vertical surfaces and penetrate deeper into porous materials.
- They improve spreadabilityand reduce runoff, making cleaning more efficient.
Using the correct combination of these three components ensures maximum effectiveness while protecting the surface and the environment.
Step 3: Application Techniques
Proper application is key to ensuring an even clean without damaging the surface.
Low-Pressure Spraying
- Unlike pressure washing, softwashing uses a low-pressure pump to apply the chemical solution evenly.
- This prevents damage to delicate surfaces like render, roofing materials, and painted finishes.
Dwell Time – Allowing the Chemicals to Work
- The time the solution remains on the surface before rinsing is crucial for effectiveness.
- Typical dwell times:
- Light organic staining: 15 minutes.
- Moderate algae and mold: 30 minutes.
- Heavy staining (black lichen, moss): Up to 60 minutes.
- Never let the solution dry on the surface as this can leave streaks or cause surface damage.
Weather Considerations
- Avoid applying softwash solutions in direct sunlight, as chemicals can evaporate too quickly, reducing their effectiveness.
- Windy conditions can cause overspray, affecting nearby areas.
- Cold weather can slow down chemical reactions, requiring longer dwell times.
Step 4: Rinsing and Post-Cleaning Care
Rinsing is a critical step in softwashing as it removes loosened contaminants and prevents chemical residue buildup.
Low-Pressure Rinse
- Always use a low-pressure water source to rinse the surface thoroughly.
- This ensures all chemical residues are removed, preventing potential damage.
Reapplication for Stubborn Stains
- If black spots or algae remain, a second application may be necessary.
- Avoid using excessive chemical strength; multiple light applications are better than one overly strong one.
Post-Cleaning Treatments
- Applying a biocide after softwashing extends the results by preventing regrowth.
- Sealing some surfaces (like driveways) can further enhance durability and protect against future staining.
Step 5: Safety Measures and Best Practices
Softwashing involves strong chemicals that must be handled responsibly.
Personal Protective Equipment (PPE)
- Wear chemical-resistant gloves to protect skin.
- Use goggles to prevent splashes from reaching the eyes.
- Respiratory masks are essential when working in enclosed spaces or handling strong concentrations.
Chemical Storage and Handling
- Store chemicals in a cool, dry place, away from direct sunlight to prevent degradation.
- Label all chemical containers clearly, including dilution ratios and expiration dates.
Environmental Considerations
- Control chemical runoff to prevent contamination of water sources.
- Use biodegradable surfactants where possible to reduce environmental impact.
- Neutralize any excess solution before disposal to ensure compliance with local environmental regulations.
Conclusion
Softwashing is a highly effective and environmentally responsible cleaning method when done correctly. By following best practices—from selecting the right chemical mix to applying solutions with precision and ensuring safety—professionals can achieve long-lasting, high-quality results.
By prioritizing proper techniques, dwell times, and post-cleaning care, softwashing remains the preferred alternative to pressure washing, offering superior surface protection and an extended clean.
Whether cleaning driveways, render, roofs, or patios, using the right approach ensures a cleaner, safer, and more durable outcome for every job.
We hope this article was helpful. For more information from SoftWash UK, please visit their CPD Member Directory page. Alternatively, you can go to the CPD Industry Hubs for more articles, courses and events relevant to your Continuing Professional Development requirements.
