If you want to remove the algae yourself, you can use a combination of chlorine bleach and warm water to gently scrub on the brick before power wash with your low pressure nozzle.
3) USE A CLEANER FIRST
I used a bleach-free pressure washer concentrate and sprayed it over each section to help loosen the grime before going at it with a higher pressure nozzle. It didn't take long to apply and helps get those stubborn mildew stains out.
Vinegar (For Basic or Interior Cleaning): Alternatively, some people skip the dish soap and mix a solution with equal parts vinegar and water, then pour it into a spray bottle. This solution can be surprisingly effective at removing basic stains from brick.
Pressure washing is great for new or particularly strong brick. Scrubbing with bleach, trisodium phosphate or buffered construction cleaner are other options. As with interior brick, it's best to avoid using a wire brush if possible. The wire can damage the brick.
Start at the top of the brick patio and work downwards. This lets you avoid streaks from dirt that may be more concentrated near the bottom of a wall or path. If you're using a detergent mix, apply it as you go down each section of bricks so that there's no residue left behind on individual bricks.
Scrubbing With Borax
For regular cleaning of brick patios, you can opt for a milder cleaning solution. Mix one tablespoon of borax with a gallon of warm water. Pour the solution on the brick and scrub with a stiff brush.
Concrete and Brick Driveways
Concrete and brick are very durable, and they can last for decades without sealing. However, if you live in a rainy, extremely cold, or fairly hot climate, applying a sealant will prolong the lifespan of these driveways.
Brick companies tell you to use low pressure when washing brick. They state around 500-1000 PSI should be sufficient enough and they also insist to never go over 1500 PSI. If you just blast the brick wall with 5000 PSI you will scar up the bricks and cause a lot of damage.
Sun Joe SPX-APC1G All-Purpose Heavy-Duty Pressure Washer
Sun Joe SPX-APC1G All-Purpose Heavy Duty Pressure Washer is a highly versatile pressure washer detergent that can clean brick and other hard, abrasive surfaces.
In a perfect world, you should wait about three to four days afterward before you start exterior painting. This gives typical surfaces like wood, brick, and other porous materials time to fully dry. It's never a good idea to paint onto still wet surfaces.
Mix Dawn and baking soda into a paste to clean detailed brickwork. For old brick, always try the least abrasive method and work your way up. Use a sturdy bristle brush when it comes to fireplace brick cleaning.
WD-40 may remove paint stuck to brick if applied directly and in large quantities, allowing it to sit on the surface for a few hours.
To clean paver slabs, you can use a detergent, such as Dawn, or a vinegar-water solution that is gentle enough to effectively clean without causing damage to your concrete pavers.
A recipient of the Safer Choice label, Simple Green All-Purpose Cleaner can be used in pressure washers and on all washable surfaces, and easily removes tough dirt and grime without the use of caustic chemicals.
Use only detergents specifically designed for pressure washers, such as: Sun Joe® HOUSE +DECK WASH. Sun Joe® SNOW FOAM AUTO WASH. Sun Joe® HEAVY DUTY CLEANER.
The key to cleaning brick is less pressure, more detergent. Bricks and mortar are porous, so the detergent and water will soak in a bit. Giving it plenty of detergent and water will help cover all areas where dirt may reach.
Our recommendation ranges from as low as 3,000 PSI to as high as 4,000 PSI.
And brick is one of the most popular choices for outdoor patios and walkways because of its rich and classic look. However, over time; dirt, grime, and even moss can cause nasty discoloration, leaving your patio looking dull and unwelcoming. Luckily, pressure washing can restore brick to its former glory.
Most Exterior Bricks Do Not Need to Be Sealed
In fact, bricks today are even better made than they were a century ago. Most do not need the added layer of protection. Mortar has also gotten stronger over time. The mortar of today creates a better seal around the brick joints than the mortar made decades ago.
Clean your bricks with a cleaning solution, or by using undiluted white vinegar. Once you've prepared the surface of the bricks, you can apply a coat of concrete stain. You can adjust it according to the original color of your bricks. You can choose from a wide variety of water-based stains and acid-based ones.