Brickwork copes with a lot in Australia: coastal salt spray, humid summers, leaf litter, air pollution and long wet spells can all leave it looking stained, patchy or green with moss. The good news is that most brick surfaces can be cleaned safely with the right method and a bit of care. The key is to match the cleaning approach to the type of grime you’re dealing with, and to avoid anything too harsh that could damage the bricks or mortar.
Before you start, check whether the brickwork is painted, rendered, sealed or bare. Painted brick and older mortar joints can be more delicate than modern face brick. If you’re unsure, start with the gentlest method and work up only if needed.
What You’re Cleaning And Why It Matters
Mould, moss and dirt each need a slightly different approach. Dirt is usually surface build-up that can be removed with water and scrubbing. Mould is a living growth that often appears in damp, shaded areas. Moss is thicker and clings into mortar joints and rough brick surfaces, especially where moisture lingers.
| Problem | What It Looks Like | Best First Step |
|---|---|---|
| Dirt | Grey film, dust, general grime | Soft brush and hose down |
| Mould | Black, green or brown spots or patches | Mould cleaner or diluted bleach solution, if suitable |
| Moss | Green, fuzzy growth, often in joints | Scrape off gently, then treat and rinse |
Always test any cleaner on a small hidden area first. Some acids and harsh chemicals can etch bricks, damage mortar, or cause colour changes that are hard to reverse.
Safe Cleaning Methods For Brickwork
1. Start With Dry Brushing
For loose dirt and surface growth, begin with a stiff nylon brush or broom. Brush the wall from top to bottom so loosened material falls away from clean areas. Avoid metal brushes on softer bricks or older mortar, as they can scratch the surface.
2. Wash With Clean Water
Use a garden hose with a gentle spray setting to wet the wall thoroughly. Pre-wetting helps reduce how much cleaner the brick absorbs. Work in sections and keep the wall damp rather than saturating one spot for too long.
3. Use A Suitable Cleaner
For mould and mildew, an outdoor mould cleaner from Bunnings or Mitre 10 can be a practical option. Follow the label carefully and use only products intended for masonry. For general grime, warm water with a little mild detergent may be enough. If you use a bleach-based solution, protect nearby plants, rinse thoroughly, and never mix bleach with other cleaners.
For stubborn stains, some homeowners use a specialised brick cleaner from Dulux, Taubmans or British Paints stockists, but only choose products recommended for brick or masonry. Avoid acid cleaners unless the manufacturer specifically says they are safe for your brick type and you are confident using them.
4. Rinse Well
After scrubbing, rinse from top to bottom until all cleaner residue is gone. Leftover cleaning product can leave streaks, attract more dirt, or harm nearby surfaces. If you’re cleaning near windows, timber frames or garden beds, shield them as you work.
5. Use Pressure Washing With Care
A pressure washer can be useful on tough dirt and moss, but it can also damage mortar, force water into the wall and chip older bricks. Use a wide fan setting, keep the pressure low, and stay at a safe distance. Never use a high-pressure jet close to mortar joints or cracked brickwork. On heritage homes or older masonry, hand cleaning is usually the safer choice.
What To Avoid On Brick
- High-pressure blasting on soft, damaged or older brickwork
- Wire brushes that can scratch the surface
- Bleach or strong chemicals mixed together
- Cleaning in direct hot sun, which can dry cleaners too fast and leave marks
- Cleaning moss or mould without fixing the moisture source first
If mould keeps returning, look for the cause: overflowing gutters, poor drainage, garden beds built too high against the wall, leaking downpipes, or shaded areas that never dry out. In some cases, a roof plumber, plumber or drain specialist may need to investigate. Plumbing work that is legally restricted in Australia must be done by a licensed professional.
Extra Tips For Better Results
- Choose a cool, overcast day so cleaners do not dry too quickly.
- Wear gloves, closed shoes and eye protection.
- Cover nearby plants with plastic sheeting and rinse them afterwards.
- Work from the bottom up only when applying some cleaners, but rinse top down.
- If the brickwork has efflorescence, be careful: that white salty residue is different from mould and may need a different treatment.
If the brickwork is badly stained, crumbling, or the mortar is soft and sandy, it may be time to get a professional opinion. A licensed bricklayer or specialist cleaner can assess whether repointing, resealing or more detailed restoration is needed. In Australia, building work must comply with the National Construction Code, and trades should hold the right licence or registration under your state or territory Fair Trading or building authority rules.
For homeowners with larger exterior projects, it can also help to compare related services and materials from Australian suppliers such as Colorbond by BlueScope, James Hardie, CSR Gyprock, Dulux, Taubmans and British Paints, depending on what else your property needs. And if you’re reading from across the ditch, our sister directory Trade Directory NZ may also be useful.
If you’d rather leave the job to a pro, find qualified local bricklayers on Aussie Trade Directory and connect with local bricklayers who can clean, repair and maintain your brickwork properly.