What roof details matter for a cleaning estimate?

The estimate form asks for a name, an email and a phone number, and then two things about the job: Service needed, with the choices Roof cleaning, Paver cleaning, Window cleaning or More than one service, and Project details, which is an open box.

The first of those takes a second. The second is where people stall, because nothing on the form says what a roof cleaning estimate needs to know. A free estimate is the point of sending it, and the three surfaces on the form are the only three the company names: roofs, pavers and windows. If the pavers or the glass are part of the same request, the More than one service choice is there for exactly that, and one estimate that covers the roof, the pavers and the windows explains how that works.

For the Project details box itself, the useful guide is not a sales checklist. It is the short list of conditions that the roofing makers and their trade associations write their own cleaning instructions around. Each step below takes one of those conditions, says which document it comes from, and turns it into a sentence a homeowner can type without climbing a ladder.

The single most useful line in Project details is what the roof is made of, because the published cleaning instructions are written one material at a time and do not agree with each other.

For asphalt shingle, the Asphalt Roofing Manufacturers Association (ARMA) describes a solution of liquid household bleach and water, left to dwell on the roof before a low-pressure rinse. For concrete tile, Eagle Roofing Products writes that “it is recommended that you use only water with the water pressure never exceeding 1200 pounds per square inch (psi).” That figure is Eagle's, for Eagle's concrete tile, and it does not carry over to shingle, to metal, or to anyone else's tile. Metal roofs have their own maker's instructions again, and what each roof maker says about cleaning its material sets the three side by side.

So the first sentence in the box can be as short as the material and the shape. A tile roof may be barrel tile, the high curved profile, or flat tile; either way, add whether it is concrete or clay if you know it, because Eagle's guidance is written for concrete tile. Shingle and metal are just as easy to name. If you do not know, say what it looks like from the driveway, and say that you are not sure. A guess stated as a fact is less useful than an honest description.

After the material, Eagle's own guidance turns on two things a homeowner can see from the ground: how dirty the roof appears, and what is on it.

Eagle's 2019 article on cleaning concrete tile puts it in one sentence: “Depending upon how dirty a roof appears and what pollutant is on the roof, it may be necessary to use a cleaner in conjunction with the pressurized water, but only in the most diluted solution possible.” In Eagle's reading, those two conditions decide whether a cleaner is needed at all, and if one is, how little of it. Eagle's 2024 spring article names the cue for starting in the first place: significant discoloration on the roof.

Nobody needs to name an organism in the form. A plain description does the job: dark streaks running down the slopes, an overall graying, a green tint, a patch under one tree, one side worse than the other. Say roughly how long it has looked that way, if you remember.

Two situations belong in the box as well. If the roof is new, or still under its installer's warranty, say so: the Tile Roofing Industry Alliance (TRI Alliance) tells owners of a roof still under that warranty to contact the original contractor for all inspections or repairs, and how soon a new roof can be cleaned has its own answer. If the request follows a storm, say that too.

TRI Alliance lists the conditions around a house that drive growth on a tile roof, and every one of them can be described in a sentence.

TRI Alliance's Roof Maintenance Guide names “location of the structure, the direction the roof is oriented to the sun and the quantity of trees, canals and lakes in the area.” For Project details, that becomes a few plain facts: which slopes take the sun for most of the day and which sit in shade, whether a tree hangs over part of the roof, and whether the lot backs onto a canal or a lake.

Access is the other condition. Eagle's owner information recommends staying off the roof, and ARMA's shingle procedure works from a ladder or walkboards where possible, to avoid direct contact with the roof surface; whether a tile roof gets walked during a cleaning is its own subject. What the box can usefully say is the number of stories, and anything that makes the edge of the roof hard to reach, such as dense plantings along the eaves or a steep drop at the back of the lot.

A roof wash drains onto whatever is beneath it, and two of the documents behind this answer write about exactly that: ARMA for the landscape, and the National Glass Association for laminated glass.

ARMA's technical bulletin tells anyone applying its bleach solution to “apply it carefully to avoid damage to other parts of the building and the surrounding landscape.” Glass is the sharper case. Impact windows are made with laminated glass, and for that glass the National Glass Association (NGA) names “Bleach (or other solutions containing sodium hypochlorite)” among the materials that may cause harm. Where a roof wash's overspray and runoff land is therefore part of the work itself, and whether the roof is cleaned before or after the windows takes up the order.

In the box, that becomes a short inventory: garden beds or hedges along the drip line, a paver drive or patio under a slope, and impact windows or doors below the eaves.