Phosphate-free

Florida DEP's best management practices for mobile washing tell a washer to "Use products that are labeled 'phosphate free'" and to use only the minimum amount of detergent or cleaner that gets the job done. That is FDEP asking, in a document written for washing vehicles and equipment.

GAF comes to the same word from a different direction. Its shingle cleaning mixture lists TSP, which GAF expands as "Tri-Sodium Phosphate-or acceptable phosphate-free substitute," so GAF's own recipe for GAF shingles allows a substitute in TSP's place without naming one.

Collier County's Code, Sec. 54-72(4), opens its list of exempted discharges with a condition, "The following discharges, provided they do not cause a violation of water quality standards:" and one item on that list is non-commercial washing of vehicles or boats with cleaners that meet four listed conditions at once, phosphate free being one.

That item is written for non-commercial washing of a vehicle or a boat, so a commercial crew sits outside it by its own terms, and a roof wash is not what it describes. The county's chapter also applies to the unincorporated county, so a City of Naples address answers to the city's own code unless the city has opted in. What counts as a discharge the county regulates is its own word: illicit discharge. Where wash water ends up after it leaves a surface is covered at runoff.

Of the roofing makers' and associations' cleaning documents read for this entry, only GAF's mentions phosphate, and GAF allows a phosphate-free substitute rather than requiring one. None of them, for shingle, tile or metal, sets a phosphate-free product as a requirement for cleaning a roof.

What the roofing makers do publish as ingredients for a roof solution is laid out at what is in a soft wash solution.