What is the right month for exterior cleaning in Naples?

Before picking the right month, rank the three surfaces by one test: does any published document tie the work on that surface to the calendar?

The ranking does most of the deciding. If the work includes a paver sealer, the calendar has something to say. If it does not, the documents give no reason to prefer one month over another, and the right time of day matters more to the glass than the right month.

The sealing condition is about moisture, and moisture is where the Naples calendar is most lopsided.

The condition itself is short: at least 24 hours without moisture before most sealers, in ICPI's Tech Spec 5, with SEK-Surebond naming select sealers of its own that tolerate a damp surface. A given sealer's label can move it, and the dry time is a condition to meet on the day, not a date.

NOAA's 1991 to 2020 normals for Naples Municipal Airport put August at 8.89 inches and September at 8.60, and simple arithmetic over the twelve monthly normals gives June through September 32.67 inches of a 49.55 inch total, about 65.9 percent. The National Weather Service Tampa Bay office puts the rainy season at May 15 to October 15 for Southwest Florida, and how firm those dates are is set out under the rainy season, defined.

Read against the sealing condition, the dry season makes a 24 hour dry window easier to find, and the wet months make it harder. A monthly normal is a thirty-year average of rain totals, though, and never a count of dry days. What has to be true before a sealer goes on is set out under the sequence and conditions of paver sealing, and what holding off until the rain eases changes is its own question: whether exterior cleaning can wait until after the rainy season.

The glass documents set a condition, and it is heat and sun rather than rain.

The National Glass Association writes: “Cleaning tinted and reflective glass surfaces in direct sunlight should be avoided, as the surface temperature may be too hot for optimum cleaning.” The PGT, CGI and WinDoor care guide puts it as a tip: “For the best results, clean your glass during cooler temperatures without direct sunlight.”

The Naples normals show why that line is never far away. The normal high runs from 74.8 F in January to 90.9 F in August. Those are air temperature averages at the airport and not a measurement of any pane, and a shaded pane on a hot afternoon is out of direct sunlight while a sunlit pane on a mild morning is not. Sun moves around a house every day of the year, so the glass condition picks an hour and a side of the house, and leaves the month open.

Where the roof is cleaned on the same property, the glass has one more condition, and no month changes it. ARMA's roof bulletin says algae discoloration may be lightened with a household bleach solution; bleach is on NGA's list of what may harm laminated glass; and PGT and Cardinal Glass describe their own hurricane glass as laminated, in the lines quoted under roof solution and impact glass on a one-visit job. Keeping roof solution off impact glass is therefore a technical requirement in every season.

The roof documents speak about recurrence, not about seasons.

TRI Alliance writes: “If the growth returns, treatment can be repeated as necessary.” ARMA writes that “The effectiveness of such cleaning is only temporary, and the discoloration may recur.” Neither line names a month, a season or an interval, and neither is a schedule.

The water rule names no month either: Collier County Ordinance 2015-27 allows exterior home surfaces and roofs to be washed “anytime” with low-volume equipment, on a drainage condition that holds all year, and the rule is quoted whole under the county washing rule on the seasons page.

The longer roof version of this question, with the roof documents laid out one by one, is the right time of year for roof cleaning in Naples.

Put the three halves together and the decision is simpler than the calendar looks.

• Work that includes a paver sealer: the drier months of the Naples normals make the sealer's dry window easier to find, and the sealer's label sets the exact condition.
• Work on glass: the hour and the side of the house, whatever the month.
• Work on a roof alone: no published document names a month.

That is the reading of the documents, and it holds in any year until the documents themselves change. How the Naples year treats a roof, a driveway and a pane of glass, surface by surface, is set out under what the Naples year does to each surface. Words like dry season, rainy season and dry time are defined one at a time in the glossary of exterior cleaning terms.