You're Probably Cleaning Your Exposed Brick The Wrong Way
If you're lucky enough to have true, exposed brick anywhere in your home, listen up: If you want to keep it around for another hundred years, then it's time to learn how to clean it once and for all. The very last thing you want to do is accidentally ruin a beautiful, aged brick wall and have to restore it. You may even find out you can't recover the exposed brick's sophisticated glory at all. According to 757Brick, some commercial grade cleaners are notoriously too harsh for brick, and can lead to serious discoloration if used improperly and too frequently. Instead, you should stick with a simple cleaning routine from the get-go to avoid any undesired staining.
So ditch the paper towels, leave the overpriced cleaners at the Home Depot checkout, and definitely grab your vacuum for those caked-on cobwebs — with a large surface area of dusty and old, worn brick, you're going to need it.
For brick walls, the proof is in the paste
Just know that while your brick wall can withstand the test of time, older mortar probably can't withstand you aggressively scrubbing it. 757Brick recommended skipping anything too abrasive for your cleaning and opting instead for something gentle, like a microfiber cloth, super soft masonry sponge, or even your bare hands. Paper towels are also a no-go for this cleaning job, since little pieces of paper may get stuck behind and cause you even more of a headache.
So what can you use on exposed brick, if not something from the store? The answer's probably already in your cabinet — all you need is some dish soap, water, and a bit of table salt, according to SFGate. You may be able to get away with a pass of warm water for newer brick, but if you need to really get through layers of grime, try mixing these ingredients together to make a paste.
Put the mixture directly on the brick wall, and keep it there for about 10 minutes before wiping it away, then give the wall another coat of just water. Home Depot also suggested wetting the wall before you cover it with the paste, since dry brick is particularly porous and will soak up whatever you place on it. It's that easy — in under an hour, you'll have your old school charm looking brand new (well, kind of).