How Much Does It Cost To Clean A Roof?

Average Cost Per Square Foot 

Cleaning a roof costs $0.20 to $0.60 per square foot. Many contractors charge by the square foot of the roof or by the square—each square is 100 square feet. The average house roof is around 2,000 square feet.

Cost Factors 

The cost to clean your roof depends on several factors, including the roof size, slope, and height, what it’s made from, and the cleaning method chosen. If your roof isn’t washed regularly or in top condition, this can push the price up too.

Additional Services 

Often roof cleaning contractors provide additional roof maintenance services. By adding these on at the same time, you might get a discounted price and they can help keep your roof cleaner and in better condition for longer. Some other maintenance tasks include:

• Moss prevention treatment: A buildup of moss on your roof can block gutters, absorb heat (increasing cooling costs), and keep shingles wet—wearing them out prematurely. Most roof cleaners remove moss as part of their service. They may also suggest applying a treatment to prevent moss from returning so quickly like zinc oxide strips. Expect to pay $100 to $300 or $0.05 to $0.15 per square foot for this.

• Roof sealant: Licensed roofing contractors can seal your roof. This helps repel water, reflect sunlight, makes it flame and corrosion-retardant, and increases its longevity. The typical cost to seal a roof is $0.65 to $5 per square foot.

• Cleaning or repairing gutters and downspouts: Blocked or broken gutters can lead to expensive roof repairs. It makes sense to have these cleaned while someone is already up on the roof. The average cost to repair gutters is $370 and typically gutter cleaning costs $160.

Labor Costs 

Labor accounts for the majority of roof cleaning costs. Your roofer may charge more for a complicated or challenging roof cleaning job, like widespread moss or algae growth, or a roof that hasn’t been cleaned in several years. If your roof is just in need of a refresh for aesthetic purposes, your roofer may charge less. 

Home Size, Height, and Location

As well as the size of your roof, its shape and style affect how much you pay. Steep roofs and those with complex designs (such as mansard or Dutch gable) take longer to clean and may require the use of additional safety equipment. Multistory houses make access and cleaning more of a challenge, so this can also increase the price. Typically these elements add $0.10 to $0.15 per square foot.

Where you live also influences roof cleaning costs. Contractors in major cities usually charge more than those in rural areas. 

Roof Condition

A roof with a thick layer or dirt, debris, and moss takes longer to clean and pros may need to use extra cleaning products. Your roof cleaning contractor will advise you when they carry out an inspection if they plan to charge extra fees.

Roof Type

Metal roofs (and sometimes those composed of ceramic tile) can handle less expensive pressure washing, whereas other types—like shingle, tile, tar and gravel, asphalt, and rubber—benefit from gentler soft washing methods to prevent damage.

Method of Cleaning 

Your roof material influences the type of cleaning method professionals will use. The two main types of cleaning include pressure washing and soft washing.

Pressure Wash 

Pressure washing might seem like an affordable way to thoroughly clean your roof, but contractors don’t often recommend this technique. With 1,300 to 2,800 pounds per square inch (psi) pressure, the strong force of the water can chip, dent, or crack the roofing material. Cleaning using this method on an asphalt, shake, slate, or tile roofcan sometimes void warranties.

Pressure washing is sometimes used on durable metal roofs, but with a machine with a lower psi. Power wash roof costs run between $0.20 and $0.60 per square foot.

Soft Wash

Soft washing is a common, gentle roof cleaning method. It’s often more expensive than pressure washing because it involves more labor-intensive techniques. Pros use low-pressure hoses (under 1,000 psi), scrub brushes and cleaning solutions to kill algae and moss. Expect to pay between $0.30 and $0.60 per square foot.

Chemical Wash

Chemical washes cost between $0.20 and $0.30 per square foot, and kill living organisms like moss, lichen, and algae. This type of cleaning doesn't use pressurized water, but rather relies on the cleaning solution to remove growth on your roof.

Low-Pressure Wash

Low-pressure washing costs between $0.30 and $0.70 per square foot. This style of washing fall somewhere between a high-pressure wash and a chemical wash. It's not as intense as a typical power washing, so it's good for shingle roofs. But there is just enough pressure to remove dirt and debris. You can also add a cleaning solution to tackle moss and algae.

Type of Roof 

Roof cleaning pros charge about $425 for all roof types. Although soft washing is the best approach, contractors use different solutions for asphalt vs. tile or metal.

Roof tiles average $425 to clean. These materials can last much longer than asphalt, but take extra care to clean without damage. Tiles made of ceramic, clay or concrete were not meant to support human weight. Hire an experienced pro to help make sure that your project doesn’t turn into a repair job.

Cleaning asphalt falls into the same range of $300 to $575. The soft, flexible shingles require a delicate cleaning approach. High water pressure can deteriorate or remove them. Soft washing with a biodegradable product removes most accumulations without damage.

Tar and Gravel

Cleaning a tar and gravel roof usually requires water and a solution that eliminates mold and mildew. Pros may use bleach, but it requires care to avoid damaging plants nearby.

Rubber

If you want to clean a rubber membrane flat roof, you’ll need liquid detergent, water and a scrub brush. Significant dirt buildup may require a special product for rubber.

Metal 

Metal roofing won’t chip or crack like tiles, but the panels can scratch or dent. Plain water with a mild liquid detergent usually works well.

The average cost for metal roof cleaning is between $0.20 and $0.70 per square foot. They are very strong and resistant, so they can withstand the high-powered blast of a high-pressure wash. This removes dirt and debris and rids the surface of most moss and lichens. Metal is capable of handling hot water pressure washing. This will be better suited to removing debris, moss, and other items from the roof’s surface.

Slate Shingles 

As with metal, cleaning slate involves water and a small amount of liquid detergent. The tiles are heavy but can crack if someone steps carelessly.

Clay 

Clay tile is a lot like ceramic, so the cleaning methods are similar. Clay is more porous, so it can’t take pressure-washing. Instead, you can use a garden sprayer with a product like Roof Wash.

Wood

Wood roofing can blow off under high pressure, so you’ll want to use a garden hose. For stubborn stains, pros often use deck cleaning products. Solutions containing oxalic acid may be rated to work with cedar shakes.

The average cost to clean wood roofs ranges from $0.30 to $0.70 per square foot. One of the issues with this material is that it does not always stand up well to high-pressure blasts of water. The best option is a low-pressure wash that will not risk damaging the material but still provides a thorough clean. Professionals use specially selected chemical solutions that are gentle to the wood and tough on moss. This can be used to remove lichen, moss, and other debris.

Ceramic Tile 

Ceramic tile may be the only type that can handle pressure-washing, due to its dense composition. Most pros still don't recommend it. To avoid damage, it’s usually better to soft-wash it with a roof cleaning product.

Concrete 

Concrete tiles are popular in temperate climates with wet weather. Moss buildup is typically the biggest problem for this material.

DIY vs. Hiring a Professional

Although you can save money cleaning a roof yourself, hiring a pro is almost always the best choice. A roofing contractor can:

• Safely navigate the elevated, slippery surface.

• Avoid breaking delicate tiles or shingles that aren’t designed to take the weight of a person.

• Use the right products for the roof material (if you use inappropriate chemicals or the wrong volumes, you could cause irreparable damage).

When you’re ready to findroof cleaning services near you, be sure to get at least three quotes and ask about experience.

FAQs

How much does roof shampoo cost?

Roof Shampoo is a biodegradable cleaning solution that isn’t sold directly to homeowners. To get an estimate, contact an authorized contractor in your area.

How much does it cost to pressure-wash or power-wash a roof?

The cost to pressure-wash or power-wash a roof runs at $425 on average.

Is it safe to power wash a roof?

In most cases, power-washing a roof can damage the material. Unless you have a metal roof, using the gentler soft washing method will avoid water-related harm.

Is roof cleaning necessary?

Regular roof cleaning can extend its lifespan by 10 to 20 years. It also improves your home’s curb appeal and helps spot problematic costly roof problems. The average cost to repair a roof is $1,000.

How long does it take to clean a roof?

Cleaning a roof takes two to five hours, depending on the size and condition.

How much does roof and gutter cleaning cost?

The cost to clean gutters is $160, plus the average of $440 to clean the roof.

How do I know when to replace roof flashing or shingles vs. washing?

Missing or damaged shingles need replacing. When the flashings leak, it’s time to repair or replace them.

How often should a roof be cleaned? 

Although many pros recommend cleaning your roof every two to five years, the frequency depends on the roofing material type and the climate and environment you live in.