Auckland’s warm, humid climate (75–85% average humidity) combined with regular rainfall creates ideal conditions for mould, algae, and lichen. South-facing walls, shaded areas, poor ventilation, overflowing gutters, and proximity to trees or bush all accelerate growth. Mould spores are always present in the air — they just need moisture and a surface to land on.

You can remove small patches with a scrub brush and diluted cleaning solution, but the mould will return within 2 to 4 weeks because DIY methods don’t kill the root system (hyphae). For full exterior walls or heavy growth, professional soft washing is far more effective and longer-lasting — treated surfaces typically stay clean for 12 to 18 months.

Yes — particularly black mould (Aspergillus, Cladosporium). It produces airborne spores that can enter your home through windows, doors, and gaps in frames. These spores trigger asthma, allergic reactions, and respiratory irritation, especially in children and the elderly. Regular removal reduces spore counts around your home.

High-pressure washing blasts the visible mould off but doesn’t kill the root system. Mould grows back within 4 to 8 weeks — often worse, because high pressure roughens the surface and gives mould more texture to grip. High pressure (2,000+ PSI) also risks stripping paint, gouging timber, and forcing water behind cladding. Soft washing below 500 PSI with a treatment solution kills mould at the root and results last 12 to 18 months.

Professional soft wash house washing starts from $199+gst for a single level home up to 80 sqm, ranging up to $449+gst for double level homes up to 400 sqm. Essential Water Blasting uses fixed-rate pricing by the square metre — you know the cost upfront before the job starts. Bundle with gutter cleaning, roof treatment, or spider treatment on the same visit and save.

Essential Water Blasting recommends a professional soft wash at least once a year for most Auckland homes. Properties near the coast, under heavy tree cover, on south-facing slopes, or with poor ventilation may benefit from washing every 6 to 8 months. Regular washing prevents the deep staining that becomes permanent if left untreated.

No. Soft washing uses pressure below 500 PSI — roughly equivalent to a garden hose with a nozzle. It’s safe for all common Auckland cladding types including painted weatherboard, Linea, brick, plaster, and concrete. The biodegradable cleaning solution is plant-safe when diluted and breaks down naturally in soil. Essential Water Blasting pre-wets and post-rinses all gardens as standard.

Mould is a fungus — it appears as black, grey, or dark patches and produces airborne spores. Algae is a plant-like organism — it appears as green, slimy films on damp surfaces. Both thrive in Auckland’s humid conditions but need different treatment concentrations. Lichen is a combination of both (fungus + algae living together). A professional soft wash technician identifies the type and adjusts the treatment accordingly.