Is pressure washing safe for brick and masonry?

Pressure washing brick and masonry surfaces on commercial, municipal or institutional buildings should only be performed with careful planning and appropriate equipment. While pressure washing is sometimes used to clean masonry, improper techniques or excessive pressure can erode mortar joints, drive water deep into the wall assembly, or strip away protective surface coatings. This is particularly consequential in New England, where freeze-thaw cycles, wind-driven rain, and high moisture levels are ongoing risks for brick and masonry.

Older, historic, or deteriorated masonry may be especially vulnerable to high-pressure cleaning, leading to surface loss, spalling, and accelerated weathering. Even structurally sound masonry can be compromised over time if water penetrates beyond the face brick, potentially leading to interior leaks, efflorescence, or hidden corrosion within wall ties or anchors.

Professional masonry cleaning typically involves a tailored approach based on the building material, condition, prior treatments, and site-specific exposures. For historic or delicate masonry, gentler cleaning systems, such as low-pressure water, specialized non-abrasive detergents, or steam, may be more appropriate to preserve both the structural and aesthetic qualities of the facade. Pre-cleaning inspections are critical for identifying areas of vulnerability, previous repairs, and appropriate cleaning protocols.

Proper maintenance of brick and masonry surfaces helps maintain water repellency, prolongs the service life of the substrate, and supports long-term building envelope performance. Planning for cleaning as part of a comprehensive exterior maintenance strategy—including inspections, repointing, and sealing—helps ensure that pressure washing, if used, supports rather than undermines the health of your masonry assets.