Removing Algae From Render: Why Soft Washing Is the Best Method ✅

By Mark Cave May 02, 2025

Removing Algae From Render: Why Soft Washing Is the Best Method ✅

If you're struggling with green or black algae stains on your rendered walls, you're not alone. In damp and shaded areas, it's a common problem—but one with a powerful and safe solution: soft washing. In this blog, we'll break down why soft washing is the best way to clean render and permanently remove algae without damaging your property. 🌿

🎯 Problem: Algae and Stains Are Ruining Your Rendered Walls

Render, whether it's K rend, monocouche, or silicone-based, is designed to give buildings a modern and clean finish. But its porous nature can attract unwanted guests—like algae, mildew, and mould. These biological contaminants do more than just look bad—they also degrade the surface over time, leading to expensive repairs or re-rendering. 😬

🔍 Why Not Just Power Wash It?

Many homeowners turn to pressure washing for a quick fix. But here’s what professional cleaners know:

💥 Pressure washing damages delicate render by eroding its surface.
🧼 It only removes surface algae—leaving spores embedded in the render to grow back fast.

That’s why professional exterior cleaning companies and trained applicators now prefer soft washing for rendered walls.

✅ Solution: Why Soft Washing is the Superior Method

Soft washing uses specialist cleaning solutions to eliminate algae, spores, and organic growth at the root—without scraping, blasting, or damaging surfaces. It’s the method SoftWash UK has perfected through years of industry experience.

How Soft Washing Works 🧪

Soft washing employs a mixture of water, surfactants, and biocides or sodium hypochlorite to deeply penetrate render and destroy algae cells at a molecular level.

Common soft washing components include:

Clever Wash Surfactant – breaks surface tension for better chemical contact
Soft Wash Pro 50 Biocide – provides long-term algae prevention
Sodium Hypochlorite – for instant kill of organics and brightening the surface

Want to learn more about how to make your own soft wash mix? 🎧 Listen to our Podcast Episode on Mixing Ratios.

🛠️ Equipment You’ll Need for Soft Washing Render

To safely and effectively soft wash render, using the right tools is essential:

Clever Injector (Dosatron) – Makes accurate chemical dosing easy
Water Fed Pole Nozzle – Ideal for applying soft wash mix to tall walls
More Soft Washing Equipment – For all job sizes and budgets

Using quality gear ensures you get pro results without the risk of property damage or plant kill 🌼.

⚠️ What About Safety and Legal Issues?

Good question! Sodium hypochlorite is a powerful chemical. Applying it incorrectly can lead to:

🌱 Harm to plants
💨 Harsh fumes
⚖️ Legal consequences if used irresponsibly

That’s why chemical handling training is vital. Start with this self-study online course to stay safe and legal: Softwash Chemical Handling Online Course.

💡 Pro Tip: Use a Residual Biocide

For long-lasting protection against algae regrowth, we recommend applying a second biocide treatment after soft washing. Products like Pro 50 DDAC Biocide provide residual protection.

Learn more on the Do Biocides Have Residual Power? episode of the SoftWash Podcast with Mark Cave 🎙️.

🌟 Expert Application vs. DIY

Some homeowners do soft washing themselves with great success. But for bigger jobs or commercial properties, hiring a trained applicator is highly recommended. They’ll have:

✅ Insurance
✅ Safety gear and PPE
✅ Top-grade professional chemicals

Want to learn how to soft wash like a pro? Enrol in our SoftWash Training Course today! 🎓

📌 Summary: Why Choose Soft Washing for Render?

Here's why soft washing is your best bet for algae on render:

✅ Kills algae at the root—not just surface level
✅ Gentle on render—no high-pressure damage
✅ Long-lasting results with residual biocides
✅ Eco-conscious and efficient

👉 Ready to Restore Your Render?

Whether you're a homeowner or a cleaning professional, SoftWash UK has the tools, training, and chemicals you need to transform your property. Don't let algae ruin your exterior—visit us today to browse industry-leading products and start your journey to a cleaner, greener home. 🧼🏠

——

Also Check Out:

← Older Post Newer Post →

0 comments

Soft Wash Calculator App

Now you can say I've got an app for that!

Available NOW Click Here To Download

Softwashing calculator is an indispensable tool for juggling complicated chemical mixes. It helps reduce wastage and keeps operating costs down by giving accurate proportions

If you are having difficulty getting your head around the maths, trying to work out what percentage of softwash you need, how much chemical, surfactant and water to add, then this is the App for you.

The Soft Wash Calculator App allows you to work out your soft wash recipe by telling you exactly how much chemical, how much water and how much surfactant to add to get the desired soft wash recipe.
It doesn't stop there!.
- It can also remix your leftover softwash to a new stronger or weaker recipe.
- all controls in one place for see at a glance operation
- ease of input via pre-loaded dials. no more calculator style typing
- instantly responds to changes of complex combinations
- works in both Litres and US Gallons
- tested for Protan and Deutan colourblind users
- links to SoftwashingUK website

Take this scenario
You started with a 1% soft wash recipe of 50 gal (or litres) for a deck clean and you’re left with 13 gallons.

You get a call from a prospective customer to clean their roof. Past experience tells you a 4% soft wash recipe is needed, but what about your leftover mix at 1%?.

Do you waste time and effort driving back to base to transfer into a standby tank?
You could consider the 13 gal as just water, top up the tank and start again.
But that’s throwing away the value of the mix and raising your overhead.

Soft Wash Calculator App to the rescue.

You get to the new job and it requires 100 gal / litres.
Switch into remix mode , confirming the 13 gal already in the tank
Move the dials to your new recipe and the app immediately updates the different amounts to add in front of your eyes including the correct amount of extra surfactant.

You now have a 100 gal / litres tank of 4% soft wash recipe ready for your roof clean job!

Not forgetting you’ve saved money too, all without stress and uncertainty . Don’t underestimate what confident calmness has on your customer putting out referrals.

The same applies if you have a 4% recipe left in your tank and you need to dilute it down to 2%. Again the app will tell you how.

Softwashing calculator will also work for any chemical recipe. For instance you can use it for Sodium Hypochlorite, Bleach, Biocide , TFR traffic film remover and degreaser. Even the mathematically-challenged rocket scientist can top up their booster tanks to new fuel mixes after launch delays caused by changing weather conditions.

Using this app you will know exactly what chemical strength to put on any surface giving you the confidence and the knowledge of a professional soft washer and you’ll save money as well.

So if you have little knowledge of how to mix a soft wash recipe then this app is for you.
If you have little knowledge of how to remix a soft wash recipe then this app is for you.
If you want to save money when mixing a soft wash recipe then this app is for you.

This app is also backward compatible to devices running iOS7. We've done this so you can re-purpose an old iPhone 4 or iPod Touch 5 for what could be hazardous work environments. Just toss one in your cleaning van's toolkit.

Once you learn the methods and procedures of how to apply the soft wash to the different surfaces that need cleaning you’ll be unstoppable!

The app also has a guide to what percentage for what surface. And if you are the lucky owner of a Clever Injector it will remind you the correct setting for the job.
However you should always consider and risk assess what soft wash recipe you need to clean the surface.

** A major iOS code-base change may require a re-purchase. The appiverse at the time will confirm our promise that we won't do so unless the necessity is apparent.

01733 736191 Voicemail