Roof Cleaning in Hillsboro, OR

Clearly Amazing cleans roofs on Hillsboro homes and businesses, with crews coming from our Portland / Tigard office. Roof cleaning here is low-pressure, and the free estimate is done on site.

Call (503) 255-2532 for a free on-site estimate.

What one Hillsboro declaration says about roofs

The Orenco Meadows declaration of covenants, conditions and restrictions, recorded in Washington County on December 20, 2005, says each owner “shall maintain their Lot and Improvements in a clean and attractive condition, in good repair.” It adds that maintenance includes “care of roofs, gutters, downspouts, surface water drainage, walks and other exterior improvements and glass surfaces.” The declaration is silent on moss, algae and pressure washing.

Those are Orenco Meadows’ words for Orenco Meadows lots. The 2005 declaration is the edition we could read, and anything adopted since is the association’s to say.

Where Hillsboro’s historic rules touch roofs

The City’s Historic Preservation page says Hillsboro recognizes two local historic districts, Downtown and Orenco, and counts 87 sites on its Cultural Resource Inventory, which it says is not an exhaustive list. Under the Community Development Code (text codified through Ordinance 6508, November 2025), routine maintenance for cultural resource structures “does not include major improvements such as replacement of siding, windows, or roofing throughout the structure.” In the Orenco Townsite Area, the standards for existing dwellings and other structures built between 1910 and 1938 say “Roofing materials shall match or be consistent with the original roof.” The City’s Joan Krahmer Historic Preservation Grant Program lists “roof and foundation repair” among its examples of preservation maintenance for owners of sites on the Inventory.

Those passages are about repair, replacement and roofing materials. The routine-maintenance section never mentions cleaning a roof, and which properties are on the Inventory is for the City to say. None of it is an endorsement of any company.

Moss on Pacific Northwest roofs, from OSU and Clean Water Services

Oregon State University publishes a Solve Pest Problems guide to moss, and the version updated May 28, 2026 says “Annual maintenance is essential to minimize moss growth on roofs and other structures.” An OSU Extension Service article, published in February 2023 and reviewed in 2025, calls moss “inevitable” on roofs in the moist Pacific Northwest. The Clean Water Services Safe Moss Control fact sheet, a two-page PDF created October 1, 2025, says moss “can hold moisture, causing leaks and other damage.”

All three are general guidance for Oregon and the Washington County area. None is about Hillsboro roofs in particular, and none names a company.

Shingle makers and their trade group

ARMA, the Asphalt Roofing Manufacturers Association, says an asphalt shingle roof should never be cleaned with a pressure washer. Owens Corning, CertainTeed and GAF, three makers of asphalt shingles, advise against power washing them. ARMA says cleaning may make a roof slippery, which is why it encourages professionals for the job of cleaning shingles. The association also advises that walking, climbing or working on a roof be left to trained professionals. It adds that the discoloration may recur.

Precipitation at the Portland-Hillsboro Airport station

NOAA’s 1991-2020 climate normals for the Portland-Hillsboro Airport station list 35.93 inches of precipitation in a year. December is the wettest month at 6.05 inches and July the driest at 0.37 inches, and November through January together add up to 16.76 inches. Those are precipitation measurements at one station. They do not say how fast moss grows on any particular roof.

Hillsboro’s housing units, by the Census count

The Census Bureau’s 2024 five-year estimates count 43,576 housing units in Hillsboro. An estimated 20,295 are detached one-unit homes (46.6 percent). Another 14,182 units (32.5 percent) are in buildings with five or more units. Those figures count housing units, and no count here tells you what a roof is made of or how old it is.

How we clean it

Roofs across Hillsboro

Roof cleaning covers all of Hillsboro.

Hillsboro roof cleaning questions