If you don’t brush away all of the dirt, don’t worry. You’ll be able to scrub away the rest as you wash the brick. Avoid wire brushes, which can leave metal scratches on the brick and cause rust or corrosion over time.
If you’re cleaning multiple bricks and are outdoors, you can hose the bricks down as an alternative. This will cause the brick to absorb the water first and keep it from becoming saturated with soap.
If you’re cleaning many bricks, you can mix a larger batch of the paste mixture using a 1:1 ratio of soap and salt. Do not mix other cleaning solvents with the paste mixture, as some combinations (like bleach and ammonia) can result in dangerous chemical interactions.
The paste layer can be as thin or thick as you want, with its thickness depending on how dirty the brick is.
Again, avoid using wire brushes to clean bricks. If you cannot scrub off all of the dirt by scrubbing, you may need to use acid or a pressure washer to clean the brick.
After washing the paste off, dry the brick off with a towel or leave the brick to air dry in a warm area. If you’re washing multiple bricks outside, you can hose them off instead.
If you need to clean the brick indoors, choose a spot near open doors or windows.
Wear long-sleeved clothes, if possible, to protect as much of your skin as possible. If you have long hair, pull it back tightly in a bun or ponytail while cleaning with acid.
If you don’t have a spray bottle, dip a washcloth in water and wipe the surface of the brick. You can also hose the bricks down instead if you’re cleaning multiple outside (like a brick wall, for instance). [10] X Expert Source Melanie GarciaProfessional House Cleaner Expert Interview. 10 October 2019.
You can buy boric acid online or from most home improvement stores. Boric acid generally comes in dry, highly concentrated packages before they’re mixed with water, so handle it carefully and check the directions for how much to add.
Avoid using wire brushes to scrub the brick, as the metallic residue can corrode it over time.
If you’re cleaning the brick outdoors, you can also wash the acid off with a hose instead. Leave any remaining boric acid in the bucket and contact your local authorities for disposal instructions. You may need to dilute it with water before flushing it away ot deliver it to a disposal center. [14] X Research source
If you don’t own a pressure washer, you can buy or rent one from some home improvement stores.
Spraying the brick before adding a cleaner will prevent it from absorbing any cleaners and corroding.
For deeper set stains, you can apply a mixture of boric acid and water instead. Make sure to wear goggles, gloves, and long-sleeved clothes and work in a well-ventilated location.
To prevent the cleaner from corroding the brick, make sure you rinse off the entire surface of the brick. If you’re working on multiple bricks, you can rinse all of them at once from the bottom up.
