Exterior Pressure Washing Cost in Southern Maryland: 2026 Price Guide

By Gray & Sons Contracting · October 8, 2026

Exterior pressure washing in Southern Maryland costs $200 to $800 for a typical single-family home in 2026, including labor, equipment, and cleaning solutions. Most homeowners in Calvert, St. Mary's, and Charles County pay between $350 and $600 to have the exterior siding, front porch, and driveway pressure washed in a single visit. Smaller jobs, a driveway only, a patio, or a short section of fence, start at $100 to $200. Whole-property jobs that include the house exterior, driveway, walkways, patio, deck, and fence run $600 to $1,200 or more depending on the total surface area, the degree of buildup, and the number of surfaces involved.

October is an excellent time to pressure wash the exterior of your home in the tri-county area. The summer growing season has left its mark, algae, mildew, pollen residue, and dirt have accumulated on siding, concrete, and wood surfaces over the past six months, and the green and black staining that develops on north-facing siding, shaded walkways, and underneath mature tree canopy is at its most visible. Cleaning these surfaces now, before winter, accomplishes two things. First, it removes biological growth that continues to degrade surfaces even during cold months, algae and mildew do not die in winter, they merely slow down, and the organic acids they produce continue to etch concrete, discolor vinyl, and deteriorate paint and stain. Second, a clean exterior heading into the holiday season and the winter months simply looks better, and for homeowners considering selling in the spring, a fall pressure wash is one of the easiest and most cost-effective ways to improve curb appeal before listing.

Pressure washing is one of the highest-impact, lowest-cost exterior improvements a homeowner can make. A house that looks ten years older than it is due to accumulated grime, green algae streaks on the siding, and black mildew stains on the concrete can look nearly new after a professional pressure wash, a transformation that takes a few hours and costs a fraction of repainting or replacing the affected surfaces. For a home improvement company like Gray & Sons, pressure washing is also a natural first contact with homeowners, we see the exterior of the house while we work, and we can identify other maintenance needs (deteriorating caulk, damaged siding, rotting trim, failing gutters) that the homeowner may not have noticed.

This guide covers the full cost breakdown for exterior pressure washing in the tri-county area: cost by surface type, cost by house size, the difference between pressure washing, power washing, and soft washing, equipment and cleaning methods, what affects pricing, DIY versus professional, and the regional factors that make pressure washing particularly important for Southern Maryland homes.

Cost by Surface Type

Different exterior surfaces require different pressures, techniques, and cleaning solutions, and the cost varies accordingly. The table below shows typical costs for each surface type as a standalone job.

Bundled pricing: Most pressure washing companies offer a lower per-surface price when you combine multiple surfaces in a single visit. A homeowner who books the house siding, driveway, and patio together will typically pay 10 to 20 percent less than the sum of the individual prices, because the setup time, travel, and equipment mobilization are the same regardless of how many surfaces are cleaned during the visit. Gray & Sons offers whole-property pricing that covers all exterior surfaces in one appointment, ask about our bundled rates when you request an estimate.

Cost by House Size

For whole-house siding pressure washing, the primary cost driver is the total square footage of the exterior walls, which is a function of the home's footprint and the number of stories.

Number of stories matters. A two-story home costs more per square foot of siding than a one-story home because the technician must work at height, using extension wands, ladders, or lift equipment to reach the upper story. The additional time, equipment, and safety considerations for second-story work add 20 to 40 percent compared to single-story work. Three-story homes and homes with steeply pitched gable ends are the most expensive per square foot due to the height and access challenges.

Pressure Washing vs. Power Washing vs. Soft Washing

These three terms are often used interchangeably, but they describe different cleaning methods with different applications, costs, and risks.

Pressure Washing

Pressure washing uses a high-pressure stream of unheated water, typically 1,500 to 4,000 PSI depending on the surface, to blast dirt, grime, algae, mildew, and stains from hard surfaces. It is the standard method for concrete driveways, sidewalks, patios, and masonry surfaces that can withstand high-pressure water without damage.

Best for: Concrete, brick, stone, pavers, and other hard masonry surfaces.

Not recommended for: Vinyl siding (high pressure can drive water behind the siding and damage the substrate), wood surfaces (high pressure can gouge and splinter wood grain), asphalt shingles (high pressure strips the protective granules), painted surfaces (high pressure can peel paint), stucco (high pressure can crack and chip the finish), and windows (high pressure can crack glass and destroy seals).

Typical PSI range by surface:

Power Washing

Power washing is pressure washing with heated water, typically 140°F to 200°F. The hot water is more effective at breaking down grease, oil, heavy biological growth, and stubborn stains than cold water alone. Power washing is less common in residential applications (the equipment is more expensive and less portable) but is used for driveways with oil stains, commercial loading docks, restaurant dumpster pads, and surfaces with heavy grease or industrial contamination.

Cost premium: Power washing typically costs 10 to 15 percent more than standard pressure washing due to the fuel cost for heating the water and the more specialized equipment.

Soft Washing

Soft washing uses low-pressure water (under 500 PSI, typically 60 to 100 PSI, similar to a garden hose) combined with specialized cleaning solutions, typically a blend of sodium hypochlorite (bleach), surfactants, and water, to kill and remove algae, mildew, mold, and lichen from surfaces that cannot withstand high-pressure water. The cleaning solution does the work, not the water pressure.

Best for: Vinyl siding, wood siding, painted surfaces, stucco, EIFS, cedar shake, asphalt shingle roofs, and any delicate surface that would be damaged by high-pressure water.

How it works: The technician applies the cleaning solution to the surface using a low-pressure sprayer, allows it to dwell for 10 to 20 minutes (the solution kills the biological growth and loosens the dirt), and then rinses the surface with low-pressure water. The result is a clean surface without the risk of water intrusion, grain damage, paint stripping, or granule loss that high-pressure washing causes on sensitive surfaces.

Cost: Soft washing a house exterior typically costs $0.25 to $0.35 per square foot, comparable to or slightly less than standard pressure washing per square foot, but the total cost may be higher because soft washing requires more product (the cleaning solution) and more time (the dwell period and multiple rinse passes).

For Southern Maryland homes: Soft washing is the recommended method for house siding in the tri-county area, regardless of siding material. The combination of humidity, shade from mature tree canopy, and proximity to the Chesapeake Bay and its tributaries creates ideal conditions for algae and mildew growth on siding, the green and black staining that is ubiquitous on homes throughout Waldorf, Prince Frederick, Leonardtown, and surrounding communities. Soft washing kills the algae and mildew at the root (the chemical solution kills the organisms, not just the visible surface growth), which means the results last longer than pressure washing, typically 12 to 18 months before regrowth becomes visible, compared to 6 to 12 months for pressure washing alone, which removes the surface growth but does not kill the underlying organisms.

What Affects Pricing

Degree of Buildup

A home that is pressure washed annually has light surface dirt, pollen residue, and early-stage algae growth that cleans quickly and easily. A home that has not been cleaned in three to five years has heavy algae, thick mildew staining, embedded dirt, and potentially moss or lichen growth that requires additional dwell time, stronger cleaning solutions, multiple passes, and significantly more labor. Most pressure washing companies assess the level of buildup during the estimate and adjust the price accordingly, expect to pay 20 to 40 percent more for a heavily soiled home compared to one with routine maintenance-level grime.

Access and Obstacles

Homes with limited access around the perimeter, close-set neighboring houses, fences, dense landscaping, and narrow side yards, take longer to clean because the technician must maneuver equipment in tight spaces. Homes with extensive landscaping beds adjacent to the siding require extra care to protect plants from overspray and cleaning solution runoff. Homes on steep lots or with challenging terrain around the foundation add time and difficulty.

Water Source

Pressure washing requires a reliable water source, typically an outdoor hose bib connected to the home's water supply. Professional pressure washers use 2 to 4 gallons per minute at operating pressure. If the home's water supply has low flow rate or pressure (common on well systems in rural areas of the tri-county area), the technician may need to bring a water tank or work at reduced flow, which can add $50 to $150 to the job cost and increase the total cleaning time.

Surface Condition and Material

Surfaces in poor condition, cracked concrete, deteriorating mortar joints, peeling paint, damaged siding, rotting wood, require lower pressures and more careful technique to avoid further damage. The technician must balance effective cleaning against the risk of worsening existing damage. If the surface is in poor enough condition that pressure washing would cause additional harm, the technician should advise the homeowner and may recommend repair or replacement before cleaning.

Sample Project Scenarios

Scenario 1: Driveway and Walkway, Waldorf Subdivision

A homeowner in a Waldorf subdivision has a 600-square-foot concrete driveway and a 150-square-foot front walkway with moderate algae staining and tire marks. The concrete is in good condition (no major cracks) and the job is straightforward, flat surfaces, good access, and a standard hose bib with adequate water flow.

Typical price most homeowners pay for this scope: approximately $200 to $300.

This is a two-hour job, straightforward, satisfying, and immediately visible from the street. The difference between a green-stained, dingy driveway and a clean, bright concrete surface is dramatic and immediate. This is also one of the most popular add-on services when a homeowner is already having another exterior project done, if Gray & Sons is at the house for siding repair, gutter work, or exterior painting, adding the driveway and walkway to the scope is efficient and cost-effective.

Scenario 2: Whole-House Siding Soft Wash, Prince Frederick Colonial

A homeowner near Prince Frederick has a 2,200-square-foot colonial (two stories) with vinyl siding. The north and east sides of the house have significant green algae staining from shade cast by mature oak trees. The south and west sides have moderate pollen buildup and some mildew spots under the eaves. The homeowner wants the entire house exterior cleaned, including the soffits, fascia, and gutter faces.

Typical price most homeowners pay for this scope: approximately $450 to $650.

The price reflects the bundled whole-house rate, the per-square-foot cost drops when the entire house is done at once versus individual sides. The job takes four to five hours for a two-person crew: apply solution to one side, move to the next side while the solution dwells, rinse the first side, and cycle through all four sides. The north side with heavy algae gets a second application and rinse. When the crew finishes, the siding looks like it did when it was new, bright, clean, and free of the biological growth that made the house look older and more worn than it actually is.

Scenario 3: Full Property, La Plata Ranch on a Wooded Lot

A homeowner in La Plata has a 1,800-square-foot ranch on a wooded, shaded lot. They want everything cleaned: the house exterior (vinyl siding), the 500-square-foot concrete driveway, the 200-square-foot rear patio (concrete), the 350-square-foot wood deck (pressure-treated pine, 8 years old), and 120 linear feet of wood privacy fence along the back and side yards. The entire property has heavy shade from mature hardwoods, and every surface has significant algae and mildew buildup.

Typical price most homeowners pay for this scope: approximately $850 to $1,100.

This is a full-day job for a two-person crew, six to eight hours to clean every exterior surface on the property. The transformation is the most dramatic of any single-day home improvement project: every surface goes from dingy, stained, and aged-looking to clean and bright. For this homeowner on a heavily shaded lot, an annual pressure washing is an essential maintenance item, the shade and moisture create the perfect environment for rapid biological growth, and going two or three years without cleaning allows algae and mildew to embed deeply into the wood grain of the deck and fence, eventually causing deterioration that requires repair or replacement rather than just cleaning.

DIY vs. Professional Pressure Washing

DIY Costs

A homeowner can rent a pressure washer from a local equipment rental center or home improvement store for $50 to $100 per day (for a consumer-grade 2,000 to 3,000 PSI unit) or $100 to $200 per day (for a commercial-grade 3,000 to 4,000 PSI unit). Cleaning solutions and surface treatments add $20 to $50. The total DIY cost for a full-property cleaning is typically $100 to $250 in equipment rental and supplies, plus the homeowner's time, which is substantial.

When DIY Makes Sense

DIY pressure washing is reasonable for flat, hard surfaces, concrete driveways, sidewalks, and patios, where the technique is straightforward (hold the wand at a consistent distance, use even overlapping passes, and work from one end to the other) and the risk of damage is low. A homeowner with basic mechanical comfort can rent a pressure washer and clean a driveway in two to three hours with good results.

When Professional is the Clear Choice

Professional pressure washing is the right call for:

House siding, The risk of damage from incorrect technique, excessive pressure, or improper cleaning solutions is high. Water driven behind vinyl siding at high pressure can cause mold growth in the wall cavity, damage insulation, and rot sheathing, invisible damage that costs thousands to repair. Professional soft washing eliminates this risk entirely.

Wood surfaces (decks, fences, pergolas), High-pressure water gouges wood grain, creates splinters, and leaves an uneven surface that traps moisture and accelerates rot. Professional low-pressure washing with appropriate cleaning solutions cleans the surface without damaging the wood.

Multi-story homes, Working at height with a pressure wand on a ladder is dangerous. The kickback from a pressure wand can knock a person off a ladder. Professional crews use extension wands, telescoping poles, and proper safety equipment to clean upper stories from the ground.

Heavily stained surfaces, Professional-grade cleaning solutions and equipment remove staining that consumer-grade equipment cannot touch. A homeowner who rents a pressure washer and cannot remove black mildew staining has often spent a full day and $100+ in rental fees for a result that is little better than what a garden hose would achieve.

Roof cleaning, Never pressure wash an asphalt shingle roof. High-pressure water strips the protective granules from the shingles, dramatically shortening the roof's lifespan. Roof cleaning requires soft washing with specific chemical solutions applied at low pressure, a job for professionals with roof-specific equipment and experience.

How to Protect Your Landscaping

Pressure washing chemicals, particularly the sodium hypochlorite used in soft washing, can damage or kill plants if allowed to contact foliage or root zones. A professional crew takes specific steps to protect landscaping:

Pre-wetting, Thoroughly soaking all plants, lawn areas, and landscape beds adjacent to the surfaces being cleaned before applying any chemical solution. Pre-wetting dilutes any overspray and reduces chemical absorption by the plant tissue.

Covering, Draping plastic sheeting or tarps over sensitive plants, flower beds, and garden areas that are directly adjacent to surfaces being treated with chemical solutions.

Rinsing, Thoroughly rinsing all landscaping, lawn, and soil areas after the cleaning is complete to dilute and flush any chemical residue.

Neutralizing, Some crews apply a mild neutralizing rinse (water with a small amount of baking soda or a commercial neutralizer) to planted areas after the job to counteract any residual chemical acidity.

When hiring a pressure washing company, ask specifically about their landscaping protection protocol. A company that does not mention plant protection in their process description is a company that will damage your landscaping.

Regional Considerations for Southern Maryland

Algae and Mildew: The Tri-County Reality

Southern Maryland's combination of warm, humid summers, moderate winters, proximity to large bodies of water (the Chesapeake Bay, the Patuxent River, the Potomac River), and extensive mature tree canopy creates one of the most favorable environments for exterior algae and mildew growth on the East Coast. The green algae (Gloeocapsa magma and related species) that stains roofing, siding, and concrete thrives in humid, shaded conditions, and "humid and shaded" describes the exterior of the majority of homes in the tri-county area for six to eight months of the year.

The result is that exterior surfaces in Southern Maryland stain faster and more aggressively than in drier, less shaded regions. A home in the open farmland of the Midwest might go five years between pressure washings with acceptable results. The same home tucked into a wooded lot in Mechanicsville, surrounded by mature oaks and a quarter mile from a creek, will show visible algae staining within 12 to 18 months of the last cleaning. For homes on heavily shaded lots, particularly north-facing surfaces, surfaces under overhanging trees, and surfaces near ponds, creeks, or the bay, annual pressure washing is not excessive, it is necessary maintenance.

Well Water and Water Source Considerations

Many homes in the rural areas of the tri-county area, particularly in southern Calvert County, much of St. Mary's County, and the rural corridors of Charles County, are on private well systems rather than public water. Well systems can have lower flow rates and pressures than municipal water, which affects pressure washing in two ways:

Flow rate limitations. A pressure washer requires 2 to 4 gallons per minute of consistent water flow. If the well pump cannot sustain this flow rate, or if running the pressure washer simultaneously with indoor water use drops the flow below the minimum, the pressure washer will cavitate (pull air), which damages the pump and reduces cleaning effectiveness. Professional crews test the flow rate before starting and may bring a water tank (typically 200 to 500 gallons) to supplement the supply if needed.

Hard water and mineral content. Well water in the tri-county area often has high mineral content, iron, calcium, and manganese, that can leave mineral deposits and staining on surfaces after the pressure washing water evaporates. Professional crews are aware of this issue and adjust their rinse technique accordingly, using a final rinse pattern that minimizes standing water and spotting on visible surfaces.

Siding Types Common in the Tri-County Area

The siding materials on homes throughout the tri-county area reflect the region's building history:

Vinyl siding is the most common siding material on homes built since the 1980s and on many older homes that have been re-sided. Vinyl siding should always be soft washed, not pressure washed, the low-pressure chemical cleaning process removes algae and mildew without the risk of water intrusion behind the siding panels.

Wood siding, including cedar, pine, and hardboard, is found on older homes and on custom homes throughout the tri-county area. Wood siding requires low-pressure washing (500 to 1,200 PSI maximum) with cleaning solutions appropriate for the wood species and the existing finish (paint, stain, or natural). High-pressure washing damages wood grain and can strip paint and stain.

Brick is common on colonials, Cape Cods, and custom homes throughout the tri-county area. Brick can be pressure washed at moderate pressures (500 to 1,500 PSI), but the mortar joints, particularly on older homes with lime-based mortar rather than modern Portland cement mortar, can be eroded by excessive pressure. A professional crew assesses the mortar condition before determining the appropriate pressure.

Fiber cement siding (HardiePlank and similar products) is increasingly common on new construction and re-siding projects. Fiber cement can be soft washed or pressure washed at moderate pressures (under 1,500 PSI). The key concern is avoiding damage to the factory-applied or field-applied paint finish.

Frequently Asked Questions

How often should I pressure wash my house? In Southern Maryland, most homes benefit from an annual exterior cleaning due to the region's high humidity and biological growth rates. Homes on heavily shaded or wooded lots may benefit from cleaning every 8 to 12 months. Homes in open, sunny locations with good air circulation can often go 18 to 24 months between cleanings. Concrete surfaces (driveways, sidewalks, patios) can be cleaned every 1 to 3 years depending on traffic and staining.

Will pressure washing damage my vinyl siding? High-pressure washing (above 1,500 PSI) can crack vinyl siding, force water behind the panels, and damage the substrate (sheathing and insulation) behind the siding. Soft washing, low-pressure cleaning with chemical solutions, is the correct method for vinyl siding and the only method Gray & Sons uses on vinyl. Soft washing cleans the siding thoroughly without any risk of water intrusion or physical damage.

Can I pressure wash in October and November? Yes. Fall is an excellent time for pressure washing in Southern Maryland. Daytime temperatures in October typically range from the mid-50s to the low 70s, comfortable for outdoor work and warm enough for cleaning solutions to activate effectively. The key constraint is water temperature: cleaning solutions work best when the air temperature is above 40°F, so late November and December are less ideal. Early October through mid-November is the sweet spot for fall pressure washing.

Does pressure washing use a lot of water? A professional pressure washer uses 2 to 4 gallons per minute, less than a standard garden hose at full flow (5 to 10 gallons per minute). A typical whole-house soft wash uses 200 to 400 gallons of water total. A driveway pressure wash uses 100 to 200 gallons. The water use is modest and is comparable to running a sprinkler for an hour or two.

Will pressure washing remove paint from my house? It can, and that is one of the reasons professional technique matters. High-pressure water directed at painted surfaces, particularly surfaces with paint that is already peeling, bubbling, or poorly adhered, will strip paint. Soft washing avoids this entirely because the water pressure is too low to peel paint. If a homeowner is planning to repaint, pressure washing is actually the recommended first step to prepare the surface, but the washing and painting should be coordinated as part of the same project.

Can pressure washing remove oil stains from my driveway? Pressure washing alone removes surface-level oil stains but often cannot fully remove oil that has penetrated into the concrete pores. For embedded oil stains, a pre-treatment with a concrete degreaser, applied before pressure washing and allowed to dwell for 15 to 30 minutes, significantly improves the results. For old, deeply embedded oil stains, a poultice treatment (absorbent material soaked in degreaser, covered and left overnight) may be needed before pressure washing. Even with treatment, some very old oil stains leave a shadow in the concrete that cannot be completely removed without resurfacing.

Should I pressure wash before painting my house? Absolutely. Pressure washing (or soft washing, depending on the siding material) is the first and most important step in exterior paint preparation. It removes dirt, chalking (degraded paint powder), mildew, and contaminants that prevent paint from adhering properly. Paint applied over a dirty or mildew-contaminated surface will peel and fail within a few years. The washing should be done at least 24 to 48 hours before painting to allow the surfaces to dry completely.

Ready to restore your home's curb appeal? Gray & Sons Contracting provides professional pressure washing and soft washing throughout Calvert, St. Mary's, and Charles County, from driveways and walkways in Waldorf and La Plata, to whole-house soft washing in Prince Frederick, Dunkirk, and Leonardtown, to full-property cleaning on wooded lots in Mechanicsville, Hollywood, and Lexington Park. We use the right method for every surface, soft washing for siding and delicate materials, pressure washing for concrete and masonry, and we protect your landscaping, windows, and outdoor furnishings throughout the process. Get a Free Estimate