The exterior surfaces of commercial office buildings face constant exposure to environmental contaminants that degrade appearance and, over time, cause structural damage. Concrete, brick, stone, and masonry surfaces accumulate dirt, biological growth, air pollution deposits, and weather-related staining that make buildings look neglected and reduce property values. For property managers, concrete and masonry cleaning is both an aesthetic and a maintenance necessity. Regular exterior cleaning preserves building appearance and curb appeal, extends the life of exterior building materials, prevents permanent staining and deterioration, maintains property values and tenant satisfaction, and reduces the need for expensive restoration or replacement. This guide covers the methods, frequency, and best practices for commercial concrete and masonry cleaning.
Types of Exterior Surface Contamination
Understanding the type of contamination affecting your building is essential for selecting the appropriate cleaning method. Common contaminants on commercial building exteriors include atmospheric dirt and dust that settles on vertical and horizontal surfaces, creating a dull, gray appearance over time. Biological growth including algae, mold, mildew, moss, and lichen thrive in damp, shaded areas; these organisms not only discolor surfaces but can also degrade masonry materials through organic acid production. Air pollution deposits from vehicle exhaust and industrial emissions create stubborn gray or black staining, particularly on lighter-colored surfaces. Efflorescence is a white, powdery deposit of soluble salts that appears on concrete and masonry surfaces when moisture moves through the material and evaporates, leaving salt crystals on the surface. This is primarily a cosmetic issue but can indicate moisture problems. Rust and metal staining from outdoor fixtures, railings, and metal flashing can create orange or brown discoloration on adjacent masonry surfaces. Grafiti and vandalism marks require specialized removal techniques depending on the paint type and surface material. Our building maintenance services include exterior surface cleaning for all types of commercial buildings.
Cleaning Methods for Concrete and Masonry
Several professional cleaning methods are available for concrete and masonry surfaces, each suited to different types of contamination and surface materials. Pressure washing (also called power washing) uses high-pressure water (typically 1,500-4,000 psi) to blast away dirt and contaminants. This is the most common method for concrete surfaces and hard masonry. The pressure level must be carefully controlled — too high can damage mortar joints, etch concrete surfaces, or force water into building interiors through cracks and openings. Soft washing uses low-pressure water combined with specialized biodegradable cleaning solutions to kill biological growth and dissolve dirt without the risk of high-pressure damage. This method is preferred for older masonry, softer stone, and historic buildings. Chemical cleaning applies specific chemical solutions to target particular types of contamination, such as muriatic acid for efflorescence, bleach-based solutions for mold and mildew, or alkaline degreasers for oil and grease stains. Dry abrasive cleaning uses fine abrasive media (sand, soda, glass beads) propelled by compressed air to clean surfaces without water. This method is used for delicate surfaces or when water usage is restricted. Steam cleaning uses high-temperature steam to dissolve and remove contaminants without chemicals or high pressure. This is an environmentally friendly option that is effective for biological growth and general dirt.
Recommended Cleaning Frequencies
The appropriate cleaning frequency for commercial building exteriors depends on location, climate, and building materials. In general, office buildings in urban areas with moderate climates should have complete exterior cleaning every 2-5 years. Buildings in areas with high pollution, heavy rainfall, or proximity to agricultural operations may need cleaning every 1-2 years. Buildings in arid climates with minimal biological growth may need cleaning every 3-7 years. High-visibility surfaces such as the building entry, storefronts, and ground-level facades should be cleaned more frequently — typically annually. Walkway and plaza areas should be pressure washed at least annually and more frequently if stained by food, gum, or other foot traffic debris. Awning and canopy cleaning should be done every 6-12 months depending on fabric type and sun exposure. Regular exterior cleaning not only maintains appearance but also allows identification of maintenance issues such as cracked masonry, deteriorating mortar, or failed sealants before they cause significant damage. For professional exterior cleaning services, explore our pressure washing and exterior cleaning services.
Environmental and Safety Considerations
Concrete and masonry cleaning must be performed with attention to environmental regulations and safety requirements. Water runoff containing cleaning chemicals, dirt, and biological residues must be contained and disposed of properly. Many municipalities require contractors to collect and filter wash water before it enters storm drains. Cleaning chemicals used on building exteriors must be chosen carefully to avoid harming landscaping, nearby water sources, or building occupants. Biodegradable, plant-safe cleaners should be used whenever possible. Safety requirements for exterior cleaning include proper fall protection for aerial work, protection of building occupants from chemical fumes or noise, and protection of passersby from falling debris or water spray. Professional exterior cleaning companies carry appropriate insurance and follow OSHA safety standards for all exterior work.
Additional FAQs
Can pressure washing damage brick or masonry? Yes. Pressure that is too high can erode mortar joints, spall brick faces, and force water into building cavities. Always use a professional contractor who understands the appropriate pressure levels and techniques for your specific building materials.
Is exterior building cleaning covered by building maintenance budgets? Exterior cleaning is typically budgeted as a capital maintenance expense rather than an operating expense. Most property management budgets allocate funds for exterior cleaning on a 3-5 year cycle, with more frequent cleaning for high-visibility ground-level areas.
When is the best time of year for exterior building cleaning? Spring and fall are ideal — temperatures between 50-80°F allow cleaning solutions to work effectively without drying too quickly (hot weather) or freezing (cold weather). Avoid cleaning during rainy seasons or when temperatures exceed 90°F.
How do I prepare my building for exterior cleaning? Notify tenants 48 hours in advance, close all windows in the cleaning area, remove or protect outdoor furniture and planters, move vehicles away from the cleaning zone, and secure any sensitive equipment near exterior walls.
About RBM Building Services: Since 1974, RBM has provided commercial janitorial, pressure washing, and exterior maintenance services across Utah, Arizona, Nevada, and Texas. Call 800.403.3564 or contact us.
