Winter can be felt in the air all across Ohio and the rest of the Midwest after these past few weeks of ambivalent weather. Take advantage of the last few weeks of mild weather before the cold sets in for good. One project to cross off your list before the cold weather sets in is cleaning and sealing your masonry. It is especially important to clean your masonry if mold is growing on it because this moss will hold water and as the temperatures fluctuate over the next few months the masonry will begin to crack due to the water freezing and thawing.
Power washing your masonry is not what I would recommend for removing moss. This troublesome growth is unsightly but not difficult to remove by any means. Should you elect to power wash, keep the PSI under 3000. Power washing will often chip brick that has already been weakened and cause more damage than good. Muriatic acid is also not what I would recommend for removing the mold because this powerful acid has the tendency to stain your brick and leave you with a more permanent unsightly mess than the mold was in the first place. It can leave behind white, powdery efflorescence.
When we are called out to clean a masonry surface, whether it be a chimney, a wall, or a section of the home in general, not only will we evaluate the integrity of the brick to see what is causing such growth (brick structures that are constantly damp or that are near standing water have a higher likelihood of mold regrowing after it is removed).
To clean mold and other unsightly stains from masonry, I recommend the ChimneyRx Safer Masonry Cleaner, which is deemed”Safer” because it is less corrosive than muriatic acid which can eat away at skin, clothing, and the brick itself as well as leave behind unsightly stains after the mold has been removed. The Safer Masonry Cleaner has easy application and has taken care of even the toughest mold growths we’ve seen yet.
After the mold is removed, it is keen to waterproof the area. Obviously, this area has proven it is likely to retain water to the point where mold can flourish. A water repellent that fills the pores of a brick surface and prevents vapors from being trapped beneath the sealer is preferred. Areas that hold water constantly or sit adjacent to standing water must be water proofed due to the extremely high likelihood of mold regrowth. If the area that you are experiencing the mold is horizontal, you MUST water proof because the water that stands on the ground after rainfall will almost certainly cause the mold to grow again.