Brick is elegant and timeless, but at times it seems like a magnet for dirt and dust. Weather, fireplace soot, mould and water stains can leave a red brick wall looking less than its best, but painting over the brick can take away its charm. Whether your red brick is old or new, revitalise it by giving the wall a good cleaning.
Tape plastic dust sheets on the floor beneath an interior brick wall so that if any cleaning solution drips on the floor it doesn't cause damage.
Put on rubber gloves and safety goggles.
Mix 1/2 cup trisodium phosphate (TSP) in a bucket with one gallon of hot water. Fill an additional bucket with clean hot water.
Dip a plastic scrub brush in the TSP and water mixture. Scrub a two foot by two foot section in a top corner of the brick wall with the solution for approximately one minute.
Rinse the area thoroughly with clean water and a sponge, dry it with a rag, and move on to the next section.
Repeat Steps 4 and 5 until the entire wall has been cleaned.
Carefully remove any plastic dust sheets you used.
Change your rinse water often to ensure that you get all the TSP solution off the bricks. TSP is available at hardware stores, and is also an ingredient in the household cleaner Spic and Span. If you don't have TSP, you can substitute one-half cup of Spic and Span powder.
Do not use pressure washers or muriatic acid to clean brick walls unless you can confirm with the brick manufacturer that these methods are safe to use. Both methods can cause irreparable damage to certain types of bricks.