Why do HOAs require roof cleaning?

The Asphalt Roofing Manufacturers Association writes, “There is no scientific evidence that algae is damaging to asphalt shingles, although it certainly affects the aesthetics of a roof.”

ARMA's point is about appearance: it finds no scientific evidence of damage to the shingle, and it names a roof's aesthetics as what algae certainly affects. ARMA's prevention page says algae and moss growth on roofs, “at a minimum, is an unsightly nuisance,” and its technical bulletin describes the discoloration as usually having “a brown to black appearance” that may be mistaken for fungus growth, soot, dirt, moss or tree droppings. Those lines are written for asphalt shingle, and they stay with shingle here.

What the dark streaks on a Naples roof actually are, and the organism behind them, is explained under the black streaks on a roof. Whether that growth does anything to tile is a separate question with its own answer on whether roof algae damages tile.

ARMA also describes roof algae that does not stay on one house.

ARMA's page on asphalt roofing systems says algae spores are carried by the wind or by animals and can spread from one rooftop to another, which is why algae growth is common throughout an affected neighborhood, and adds, “The same is true for apartment or condominium complexes, townhouses or row houses.” That is ARMA's account for asphalt shingle, and it describes discoloration shared across a neighborhood.

ARMA is just as plain about the limits of a cleaning. Its bulletin says discoloration on asphalt roofing may be lightened with a solution of household bleach and water, and that “The effectiveness of such cleaning is only temporary, and the discoloration may recur.” ARMA prints no interval for doing it again. Why one house on a street stays clean while its neighbor streaks is answered under why a neighbor's roof stays clean.

Florida law does not tell homeowners to clean a roof. A community's covenants may, and the statute sets the terms for when they can.

The section is titled “Architectural control covenants; parcel owner improvements; rights and privileges.” Section 720.3035(1)(a) permits an association, or an architectural, construction improvement or similar committee, to enforce standards for the external appearance of a structure on a parcel only to the extent that authority is “specifically stated or reasonably inferred” in “the declaration of covenants or other published guidelines and standards authorized by the declaration of covenants.” The everyday name for that body is architectural review committee.

The declaration of covenants is a recorded instrument running with the land, and 720.305(1) makes each member, and the member's tenants, guests and invitees, subject to it. A roof cleaning requirement, then, is a clause some communities have written and others have not. That state law itself asks for no clean roof is set out with the other Florida rules on roof cleaning.

The same subsection that allows an appearance standard also puts a condition on how it is used.

Section 720.3035(1)(a) says an association or its committee “must reasonably and equitably apply and enforce on all parcel owners” the standards the declaration or its published guidelines authorize. A roof standard in a homeowners association is therefore a community-wide rule by design. It is not written for one house.

What no statute and no roofing document can supply is the reason a particular community adopted its standard. That reason, where it is recorded, is in that community's declaration, and its guidelines, and the manager who keeps them is the person to ask. What happens once a letter about a roof actually arrives is walked through under responding to an HOA roof cleaning notice.