Is it All Right to Pressure Wash My Roof?

Pressure washing is one of the many options available to clean a roof; a high-pressured stream of water will get rid of all types of debris. Yet according to professional roofers, using it as a way to clean a housetop should be given a huge “No,” as that action could potentially damage the entire upper structure. There are instead better and safer ways to remove dirt without damaging the finishing layer.


Pressure washing is done by spraying a powerful stream of water directly onto the roof’s finish. This approach is generally not approved as a method of cleaning the roof because that portion of a house is simply not designed to withstand such water pressure. For example, asphalt shingles may seem durable; the truth is that the tiny minerals embedded on the top layer can be easily washed off with pressurized water. Those minerals play a vital role in protecting the asphalt from UV rays and keep it from becoming brittle too soon. Once the minerals wash off, the life span of asphalt shingles will decrease considerably.

Pressurized water can also move the individual shingles from their position, which could cause leaks and damage the underlying structure. If used on an older roof, the high-pressured stream of water can even break brittle shingles and cause more harm than good. Using pressurized water as a method of cleaning has more risks than benefits and should never be tried on any type of roofing finish.

Better Alternatives

Cleaning a roof can be better done using a good old broom and brush. The broom should be used to get rid of some of the larger debris, such as leaves that may have landed on the roof as well as any thick layers of dust. A soft bristled brush can then be used to remove the stubborn dirt and moss that may have compacted between the ridges and the gutters. While this approach is painstakingly slow, it is much better than repairing the damage caused by pressure washing.

Safety Guidelines

In maintaining a roof, it is important to always be aware of the dangers that come with the job as sloped ones are very risky and can lead to falls if safe practices are not followed. Following are some helpful hints to use whenever working on the top structure of a house.

  • Wear Rubber-Soled Shoes – Shoes with rubber on the soles should be used when cleaning the roof to prevent slipping. This is particularly important on a sloped roof, as rubber soles provide the best traction rather than walking on the structure barefoot or with another type of shoe. It will also protect feet from being punctured in case sharp metal such as nails are protruding from the surface.
  • Use a Safety Harness – Attaching a safety harness should be the first priority when on a roof. The safety harness will provide protection if a fall were to occur. It serves as a fall-arrest system that prevents a person from falling directly to the ground.
  • Use a Plank – Walking on top of the roof could damage brittle shingles and even cause a cave-in on weakened ridges. To avoid this type of scenario, it is important to use a plank when moving from one side of the roof to another. A plank will ensure that weight is distributed evenly on a wider area, leaving very little risk of damage occurring.

If a roof is too steep to scale, the best way to get it cleaned and inspected at the same time is by hiring a professional roofing contractor who can perform the necessary cleaning without damaging the roof. Hopefully the information provided above has provided some basic information about the consequences of pressure washing, alternatives to pressure washing, and safety guidelines that should be followed when cleaning the structure! If nothing has been learned, remember that it is not all right to pressure wash a roof!

Are you looking for a Houston commercial roofing company to inspect your roof? Schulte Roofing of Navasota services the greater Houston area and can help all customers with their roofing needs!