Take a good look at the outside of your house. Notice the green fuzz creeping up the side? Or maybe the dark smudges clinging to the walls? What you’re seeing isn’t just dirt. It’s a living, breathing ecosystem. Your home has become a playground for mould, algae, and grime. These silent squatters don’t just sit around—they spread. They stain. They even destroy.
So, get ready to explore the gory details of what’s really growing on your walls, and how expert house washing can help.
The Truth: Your Walls Are Alive
You may think your exterior is just a static surface. Paint and plaster. Brick and siding. But every wall outside is exposed to the elements. Rain, wind, humidity, and pollution collide on the surface. Over time, those walls turn into the perfect canvas for microscopic troublemakers.
Moisture is the first culprit. It seeps into tiny cracks and pores. Shade from trees or neighbouring buildings keeps things damp. Dust settles. Airborne spores float by. Before you know it, your house becomes a home for grime and biological growth.
These aren’t just ugly blemishes. They’re infestations.
Mould: The Sneaky Destroyer
Mould is not just something that grows on old bread. It thrives outdoors, especially on your house. It appears in blotchy patches—grey, green, or even black. It hides in corners. It sneaks beneath gutters. It loves dark, wet places.
Mould is a fungus. It reproduces through spores. These spores travel through the air. When they land on a moist wall, they settle in like unwanted tenants. They feed on organic matter. That includes dust, wood fibres, and even some paint types.
Mould doesn’t just look bad. It’s hazardous. Some types release mycotoxins. These can trigger allergies, headaches, and breathing issues. If your house has mould, it’s more than a cosmetic problem. It’s a health hazard.
Algae: The Green Invader
At first glance, algae might look harmless. Just a green tinge, right? Think again. Algae are plant-like organisms. They thrive in damp, shaded areas. You’ll often find them on the southern or eastern sides of homes, especially under the eaves.
Algae spread quickly. A single patch can turn into a wide green sheet within weeks. Their cells contain chlorophyll. That’s why they look so lush and leafy, but don’t be fooled.
- They can degrade your home’s exterior.
- They trap moisture.
- They cause staining.
- They eat away at paint and coatings.
- They create a slimy surface that invites other organisms, including mould, mildew, and lichen.
Dirt: The Silent Accumulator
Dirt might seem like the least offensive of the trio. After all, it’s just soil, right? Wrong. The dirt on your walls is not garden-variety soil. It’s a cocktail of pollutants. Dust, vehicle exhaust, pollen, spider webs, bird droppings, and industrial residue all get mixed together.
This layer builds slowly. It creeps in unnoticed. It dulls paint colours. It holds moisture. It creates a sticky film that allows mould and algae to grow faster. Dirt may not smell or spread illness, but it opens the door for other, nastier guests.
Neglecting this layer leads to permanent staining. It also makes house washing more difficult later. The longer you leave it, the harder it is to clean.
The Role of Climate and Environment
Where you live makes a big difference. Homes near forests are more prone to algae and moss. Coastal homes face salty air and humidity. City houses get pounded by pollution. Suburban homes get dust from nearby construction.
Even the position of your house matters. North-facing walls stay damp longer. Areas under shade dry slowly. If you have poor drainage or clogged gutters, you’re inviting all three enemies.
Each climate brings a new battle. Each environment sets a different trap. But they all lead to the same outcome: walls that look tired, old, and uncared for.
How Do They Spread?
Mould and algae don’t just appear out of thin air. They travel. Spores float freely. Wind carries them. Birds, insects, and rainwater help too. Once they land, they start their dirty work. They multiply. They crawl across surfaces.
Algae thrive with sunlight and moisture. Mould likes shade and still air. Dirt acts as a glue. Once a patch forms, it becomes a growth zone. Your wall becomes a living colony.
They don’t stay in one place either. They creep. They follow the trail of moisture. They climb up walls, slink across windows, and seep into cracks.
What Can You Do?
Start by observing. Walk around your home every season. Look for streaks, patches, or discolouration. Focus on shaded areas, gutters, and corners.
- Keep the exterior dry.
- Fix leaks.
- Unblock gutters.
- Trim trees to let the sun in.
- The less moisture, the less growth.
When cleaning, resist the urge to use harsh chemicals. You might damage the paint or harm your garden. Go for eco-friendly cleaners. Better yet, call the professionals. They use specialised equipment. They know which method suits your walls—soft washing or pressure washing.
Soft Washing vs. Pressure Washing
Not all walls are the same. A timber wall can’t handle the same pressure as a concrete driveway. That’s why two methods exist.
- Soft washing uses low-pressure water and specialised detergents. It gently removes mould, algae, and dirt. It’s best for painted surfaces, roofs, and wooden walls.
- Pressure washing blasts away grime using high pressure. It’s ideal for brick, concrete, and stone. It removes deep-rooted dirt quickly.
The key is knowing which one to use.
Keep It Clean—Stay Ahead
Maintenance is the magic word. Don’t wait until your house looks haunted. Schedule regular washes. Most homes need one every 12–18 months. High-humidity areas may need two per year.
By staying ahead, you save money, protect your investment, and keep your home looking brand-new.
Final Thoughts:
Your house is more than four walls. It’s your biggest investment. Letting mould, algae, and grime take over is like inviting rot to dinner. These invaders don’t just tarnish the view. They eat away at your home’s heart.
So take action. Call the experts at ABS Cleaning and get your house washing done before it’s too late.
